[narrator] We live in a world our ancestors would barely recognize. Around the globe, the impact of human ingenuity is now everywhere. We've pushed back
the limits of our planet at speeds, depths and heights that would have left
our forbearers breathless. Driving all these achievements is humankind's extraordinary gift for invention. Through genius and inspiration, we've created exceptional solutions
to complex problems. From the everyday to the spectacular. Some good and some not so good. This series celebrates the million ways our great inventions have transformed our world. [male voice]
That's one small step for man, one giant leap for mankind. [narrator] Every second of every day, pulsing beneath our towns and cities, are subterranean highways transporting people and goods great distances at incredible speeds. Over the centuries,
it's transformed mass transit, altered landscapes... This was literally groundbreaking. [narrator] ...and paved the way for engineering firsts. They couldn't go over them
or through them. They had to go under them. [narrator] From Victorian steam trains
chugging through the first underground tunnels to passenger-carrying pods
hurtling through vacuum tubes faster than the speed of sound. People are calling it
the fifth mode of transport. [narrator] This is the story
of the invention of the subway system and the incredible concepts which will
continue to transport us into the future. [high-octane music plays] [narrator] New York City. This concrete jungle is teeming
with more than eight million people, making it the largest metropolis
in America. It's a global epicenter built on pace. But long before it became an iconic city, the Big Apple was under siege. From the mid 1800s,
through to the early 20th century, America's industrial revolution
transformed the country. Innovations in steam, rail and the textile industry thrust the nation into the spotlight. Nowhere was feeling this prosperity more than New York City. Thanks to its positioning
as a major port, this young metropolis was fast
establishing itself as a global hub for trade and commerce. And with that, came mass migration. In just 70 years, the city's population
had risen from 33,000 to almost a million. The city of New York
was expanding rapidly. Business was booming,
and it was a city massively on the up. If you wanted a job,
if you wanted to get ahead, if you wanted to fulfill
that American dream, New York was a city
with all of those opportunities. [narrator] But this boom in business
and prosperity came at a cost. Congestion. If you wanted to get around in Manhattan, you could either take one of the
horse-drawn vehicles, public or private, or you could use your feet. The problem is,
those two things are not compatible. The amount of traffic was incredible. And there's stories of people
taking half an hour to cross the street, because they just couldn't
get through the traffic. [narrator] With the congestion problem
showing no signs of abating, New York City needed a solution. So, at the time, there was no actual way of transporting people
through the city en masse. And, well, that's what New York needed
if it was to get any kind of relief from all these people on the streets. [narrator] Under mounting pressure
to reduce overcrowding, the local government
turned to a mode of transportation that was gaining traction across America
and the United Kingdom. The steam train. The first proper steam trains
ran about 1830, both in the UK,
Liverpool and Manchester Railway, and in America. So they've been around about 40, 50 years by the time New Yorkers wanted to relieve their traffic problems on their roads. [Boeree] They did have a rudimentary
steam-powered railway system, but it only served
the outskirts of the city. There was nothing in the center itself. And they thought initially, "Well, can't we just run them like trams
along the main avenues?", and found there was just too much traffic.
Too difficult, too crowded. A steam engine is incredibly powerful, but it's also incredibly hard work to run. It takes a load of people,
a load of effort. And it produces smoke and steam and soot and all the other nasty stuff that you don't want blowing in your face
as you're trying to get to work. Now imagine the steam
in the middle of a town. Imagine it in people's faces,
in the shop fronts, in your houses. It just wasn't a viable option. [narrator] To avoid clogging the
metropolis with tracks and steam trains, engineers came up with a novel idea. The first thing that comes to mind
when you think of New York is skyscrapers. They know how to build up. And so they thought, "Well, if we can
build upwards with our buildings, why can't we put our railways
up high too?" [narrator] Engineers proposed
a series of railway tracks two stories high
running through the city. It would be known
as the elevated railway. The elevated railway brought the idea that instead of
fighting your way through the traffic, you could fly nine meters above it on a specially created train
on tracks of steel that took you above everyone else's head. [narrator] In 1867, work on the new
transport system began in earnest. The giant steel structures
upon which the steam trains would run were made up of a series
of columns and crossbeams. Positioned on top were girders
to which railway tracks were attached. In 1871, New York city's first
elevated steam train opened for business. Running along Greenwich Street, it was a roaring success. [woman's voice] So the real answer
to this growing population was to move everyone two stories up. And that became what, essentially,
was the solution to transporting people around the city. [narrator] In the following years, more elevated tracks
were built throughout the city. As New Yorkers finally got moving, across the Atlantic,
London had been suffering from the same problem
as its American neighbor. But a revolutionary solution
was just around the corner. [narrator] Much like rush hour today in central London, during the latter part
of the 19th century, the capital
was dealing with mounting congestion after its population had doubled
in just 50 years. [Arney] This caused huge problems
with so many different parts of city life, but transport was one of the biggest. The typical forms of transport
were horse drawn at street level. Things like stagecoaches,
hackney carriages and hansom cabs. It was an incredibly crowded
and sometimes quite hazardous environment. And life as a pedestrian
was quite difficult. [narrator] The large amount of horses led to a messy situation
for harried Londoners. [Arney] Apparently, three million tons
of horse manure filled the streets. Just imagine walking through that
on your way to your day job. [narrator] With the city's population
continuing to surge, the government needed to find a way to ease the crush. But unlike New York, building an elevated railroad system
in the middle of this illustrious capital was out of the question. The architecture was too historical
and too beautiful to be tampered with. And also, Londoners were a bit too posh to have something like that
ruining their beautiful city. [narrator] One Londoner
who was all too aware of the congestion problems
choking the capital was solicitor and social campaigner
Charles Pearson. One of the rather eccentric parts
of this story is that Charles Pearson, a solicitor, not a profession that usually
concerns itself with engineering, was very anxious to see
that London could spread further out. Did he have shares
in a construction company? No. Did he come from a family
of tunnel diggers? Not that I know of. He was just a solicitor who had a vision. [Wolmar] And he realized that you
couldn't build a railway on the surface, because the roads
were too crowded already, and it would have involved
demolishing lots of houses. [narrator] Instead,
Pearson put forward a bold idea. Rather than building
a railway line up above, why not go underground? [Wolmar] At the time,
there were very few tunnels. There was one built
by Marc Brunel underneath the Thames, the world's first tunnel
underneath a river. But essentially, tunneling was really not
a well-developed technique. [narrator] Unlike Brunel's Thames Tunnel, which was used by pedestrians
and as a tourist attraction, Pearson's proposal was for underground
tunnels solely for mass transit. There was no transport system
anywhere like this on earth, so it was completely revolutionary. [narrator] In 1853, Parliament approved a bill to construct
the first subterranean railway between Paddington in the west
and Farringdon in the east. Seven years later, work began. To build the underground tunnel, laborers used a method
simply known as cut and cover. The cut and cover method
is really what it says on the tin. You cut a hole in the roads, you make a big trench, you lay in the railway tracks and then you cover it over again,
making it into a tunnel. And then the road is used again
for the vehicles on top of it. So, you know, even today, there's probably hundreds of thousands
of vehicles that go over the Euston Road, and people don't know that there's a railway underneath them. Remember, they were doing this
without electricity, so it was a really simple
but effective method. [narrator] Throughout the 1850s, despite work going at full steam ahead, word on the street
was that no one would use this new subterranean mode of transport. You know, we're naturally afraid
of confined places, dark places, rats. And all of the images
were conjuring up these things. Also, of course,
the media, just like today, back in the 1800s
knew it would get more of a response the louder,
the more sensationalist it was. And this provided not only a chance
to kind of play on people's fears, but also this kind of fear of the new,
fear of the unknown. [narrator]
But any fears were soon put to rest. On January 10, 1863, the first underground transport system
in the world opened to the public. Named the Metropolitan Railway,
it used steam locomotives, which ran along
five and a half kilometers of line beneath central London. There was so much doubt
about whether this solution would work. But within the first year, 11.8 million
people used this train system. That's over four times
the population at the time. It was a total game changer. I think those first passengers
would have felt like real pioneers. Don't forget, people weren't traveling
that fast right at that time. This was completely new. They would have felt like this was a new frontier for,
not just themselves, but for humanity. [narrator]
The world's first underground was a hit. Over the next two decades,
new lines were added and extensions built across the capital. [Brosnan] Being able to rapidly expand
the underground railway so quickly from the 1860s onwards
was a massive engineering achievement. [narrator] Thanks to the Underground's
runaway success, throughout the latter part
of the 19th century, construction of new lines
dominated the city's roads. And that brought chaos. [Arney] Cut and cover
is a nice, easy method, but not when you try and do it
in central London. So you have to disrupt everything
to create these trenches. You have to knock down buildings. You might accidentally destroy something
that's just been built, like Joseph Bazalgette's new sewers. Trying to do something like this
in the middle of a busy residential city is always gonna be a disaster. The roads were very crowded. There were now water mains, gas mains
and so on, which would get in the way. It was realized that the way
of building underground railways through cut and cover
was no longer feasible. [narrator] London's Underground
was running out of room. Desperate to continue expanding, developers came to a bold conclusion. [Arney] There was only one solution:
They had to dig deep. [narrator] But if engineers were to
construct a network of new tunnels deep underneath the city of London, they'd need
an entirely different approach. [Wolmar] They needed a method that ensured you both progressed in the tunnel,
you cut the tunnel, but also, you shored it up straight away. [narrator]
To build the deep subterranean channels, engineers look to the man responsible
for the Thames Tunnel. French engineer Marc Isambard Brunel. The story behind how he came to invent a groundbreaking piece
of tunneling machinery started with an unlikely creature. So before Brunel built the Thames Tunnel,
he was actually working in a shipyard. And it was there that he noticed this type of mollusk
known as Teredo navalis, which is actually a kind of shipworm that would sort of burrow its way
into the wood of the ships. It had a sort of hard shell
around its head that would dig its way through the wood. But then, geniusly,
its excrement would come out the back and sort of line the outside of the tunnel so that it would maintain its structure
and not collapse. [narrator] Inspired by the actions
of the Teredo navalis, Brunel invented a vital piece
of equipment, which he used to tunnel under the Thames. It's named the tunneling shield. The tunneling shield
was this huge rectangular structure laid up against the surface
that you're trying to dig through. And it's split into cells. And each of these cells
has one man with a shovel. And they busily dig away at that section. And when they've dug
a certain amount forward, the next cell opens up,
and that person digs away. And then the next cell. Until that whole surface behind
the tunneling shield has been dug out. And then the shield gets jacked forward,
and you start the whole process again. Meanwhile, another team of folks
would go along behind the diggers bricking up the roof and the walls
of the tunnel to ensure that it didn't collapse. So it was an incredibly efficient system
of building a safe tunnel. [narrator] Brunel's shield
went on to pave the way for modern
mechanized tunnel boring machines, which are used today in multi-million dollar projects
all over the world. So it's amazing to think
that these giant tunneling machines that we see today
were just inspired by a little worm. [narrator] Back in the late 19th century, as the London Underground's
first deep tunnels were being built, Chief Engineer James Greathead helped to adapt
Brunel's tunneling shield, making it cylindrical in shape
rather than rectangular. This change gave birth
to the first circular-shaped tunnels, as well as a popular nickname
for the London Underground that today is used
by locals and tourists alike: the Tube. Engineers may have solved the problem
of deep tunneling, but there was a health issue to overcome: the suffocating steam. Deep tunnels were fantastic, but what
wasn't so great were steam trains. Imagine being trapped on a platform
or inside a train where there's smoke and steam
and heat and sulfurous fumes blowing at you the whole time
you're on that transport. [narrator] With deep-level tunnels
being narrower and much lower underground than their subsurface predecessors, it was clear to developers
of the late 19th century that steam trains
were no longer a viable option. You can't really have steam engines operating in very narrow tunnels
without much ventilation, because, simply, people would have certainly coughed a lot,
if not choked to death. [narrator] But as luck would have it, in the 1880s, at the same time
that these deep tunnels were being built under London, the country had been introduced
to a revolutionary form of power that was transforming the lives
of millions. Electricity. [Brosnan] There was an element
of luck and good fortune to the timing of being able to, you know,
tunnel at that sort of deeper level and the invention and practical use
of locomotives in that railway. [narrator] In 1890, when the
City and South London Railway opened at more than 12 meters below the surface, not only was it the first deep-level
underground train in the world, but it was also
the first major electrified subway line. Ironically,
because electricity was in its infancy, when the City and South London Railway
first opened, most stations were still lit by gaslight. As for the new electric underground, power was supplied to the train line
by giant generators based on Thomas Edison's dynamo motor. Located at Stockwell Power Station
in South London, they generated enough electricity
to power 14 locomotives. From the power station, the electricity was carried down the line via a third rail, positioned between
the two existing rails. The electricity was then transmitted
to the train through what's known as a sliding shoe, a device which collected
the current from the rail and transferred it to the train. The new electrified tube line
was a huge success. Other lines soon followed suit. Electric trains
were an absolute revelation. They were faster. They were cleaner.
They were cheaper to run. And they were so much more pleasant
for the passengers. [narrator]
Electrified underground locomotives propelled transportation
into the 20th century. But it's not just London
where this revolutionary transformation was taking place. [narrator] Cities such as Berlin, Paris, Budapest and Boston were also opening
their own subway systems, making them global leaders
in underground mass transit. Meanwhile, at the end
of the 19th century in New York, the once-popular elevated railway,
now abbreviated to the "el" train, was falling out of favor with the public. People started to dislike the el train
because they were loud, they were big, they were puffing out steam
and smoke right above your head, and it cast shadows all over the city. [narrator] For New York to become
the thriving metropolis that it is today, its tracks would have to go underground. New Yorkers heard
that Boston, Paris, Budapest all had underground railways, and they had to keep up with the Joneses. [narrator] But, in addition to building
their own subterranean transport network, the New York Subway
would go one step further. [Arney] New York didn't just make
their own subway system, they made it better than anyone else's. They learned from all the other cities
that had a simple two-track system, one going one way,
one going the other way. For New York, that wasn't good enough. They had to have four. An express track
going fewer stations much faster, and then two slower tracks. The big advantage of that is
it allows trains to be express trains, skipping out some of the stops and going faster from one end to another. [Arney] If one train broke down,
they had an extra track to be able to reroute trains, and they wouldn't ruin
every commuter's day. [Wolmar] And also, you can close a couple
of tracks for maintenance overnight but keep the other ones open. So that's one of the reasons
why New York has an all-night subway. [narrator] On October 27, 1904, New York City's subway
opened to great fanfare. Initially, the network had 28 stations. That figure has since exploded to 468, making it the largest subway system in the world. But today, maintaining New York's subway, which connects the island of Manhattan
to its surrounding boroughs, is no easy feat. Especially when it comes to trains
which run beneath the riverbed. To ensure that water
doesn't leak into the system, more than 750 pumps
are positioned beneath the tunnels. They run 24/7 to divert over 49 million liters of water into the surrounding sewers. Without them, the network would flood
within a matter of hours. But it would take
another technological innovation to allow global subways to expand. [narrator]
Back in the early 20th century, subway systems across Europe and America were growing at a rapid pace. More people than ever before were heading underground to get from A to B. But as more deep tunnels were built,
a new problem emerged. [Sokale] Some of the underground stations
had more than 100 steps. Imagine doing that every day
during rush hour. It must have been so exhausting. [narrator] Despite some stations being equipped with elevators, they had their limitations. [Brosnan] A lift can only fit
a certain number of people. It takes a while to wait for it
to come up and down. And obviously,
being able to convey tens, hundreds, potentially thousands of people
deep underground at greater volume and at greater speed was a vital part of a deep-level tube line
working properly. If you've ever been through one of those
few underground stations in London that still just have lifts
as the only way, you'll know how miserable
of an experience it is. You have to wait for ages to get in,
and when you do, you're all crammed in. And so, that was the situation
for everybody all the time,
trying to get the Underground. Not fun at all. So once the tube railway started getting used much more heavily, the bigger stations,
the more popular stations, needed a better way to get people
down and up from there. [narrator] But there was a new piece
of machinery in the works that looked set to take commuters
to new heights. The moving staircase. We don't know for sure who
the actual inventor of the escalator was. So we can't pinpoint it
on anyone in particular. But we do know that in the 1850s,
a chap called Nathan Ames patented an invention
for something called revolving stairs. [narrator] Ames's patent showed plans
for a vertical walkway with steps mounted on a continuous belt,
which would turn when operated. But, of course, this was prior
to the days of electricity, so in order to operate it, it would
have needed some kind of hydraulics or mechanical operation system. And as far as we know,
no working prototype was ever built. [narrator] Throughout the latter part
of the 19th century, various designs and patents
were submitted and prototypes showcased. We do know that there was some kind
of moving staircase, escalator thing in Coney Island back in 1896. But, as far as we know, it was more
of a novelty fairground attraction than an actual working escalator. [narrator] It wasn't until 1900,
at the Paris Universal Exposition, that the idea of the escalator
really began to gain attention on a global scale. Paris had a great world exhibition showing all the latest inventions. And one of these that was displayed was a kind of flat escalator,
what we'd now call a travelator, which, basically,
people got on a sort of conveyor belt and were taken along
without having to walk. You see people stepping on
and stepping off and trying it out for the first time. It must have been so exciting
to be one of the first people to try out this brand-new
piece of machinery. [narrator] But the device that took
the grand prize for innovation was Otis Elevator Company's escalator. Passengers were charged one penny
to ride up and down the working model, resulting in thousands of people
taking their turn on the motorized staircase. And it was this model that, well, gave birth to the escalator
as we know it today. So an escalator
is actually rather interesting. It's basically a conveyor belt,
and it runs around two gears. Imagine two cogs,
and the gear is run by electric motor. And basically, it goes round the gears. But obviously, it's an escalator,
so it's tilted like this, at an angle. At the bottom and top of the escalator, the stairs collapse, creating
a flat platform for the user to get on and to get off. [narrator]
Soon after the Paris Exposition, metro system bosses realized
that the escalator could be the answer to commuters' woes and began installing them
at their stations. The introduction of the escalator
was really important to be able to convey large numbers of people deep underground. That technology really sort of transformed
how commuting was experienced. [narrator] By the 1930s,
major cities across the world had their own subway systems.
Including Moscow. But while many global stations were designed with simplicity
and function in mind, the Soviet capital had other plans. Under the rule of Joseph Stalin,
prominent architects and artists were employed
to design grand palatial stations in order
to highlight Russia's superiority to the rest of the world. Today, many of these
historical stations still stand, giving the feel of traveling
through an art gallery or museum rather than a train station. Back in the middle of the 20th century, as many cities were expanding
their subway networks, their roots were becoming more complex. Nowhere was feeling this more
than London. In the 60 years
since its first line opened, the number of stations
had increased from seven to over 200. These stops were spread
across eight different lines. But how to navigate this vast network presented new challenges
that needed to be overcome. [narrator] Despite having a map
to help commuters get around the London Tube network, many people still had difficulty
making sense of it. The first two maps were a bit of a muddle. They were actually really hard to follow
for the average passenger. [Wolmar] One of the problems
with the Underground map is how do you represent it? How do you actually make it
understandable? Because once you get
more than three or four lines, it becomes very complex. And with all these wiggly lines,
you don't quite understand where you're going
or where you're coming from and so on. They showed parks, landmarks and overground railway lines. And each line would show the actual curve
that the Tube line went in. [Papadopoulos] Obviously, you know,
reading maps is something as old as time, something that we all do. However, in order to feel comfortable
doing it, you need the simplicity, right? You kind of think of the classic compass,
and you know which way you're going. It's simple, it's clean, it's clear. At that time, it was like dropping
a bunch of spaghetti onto a piece of paper and saying,
"Try and find your way around." [narrator] Convinced there had to be a better alternative, in the early 1930s,
one man took it upon himself to redesign the London Underground map. Harry Beck was an electrical draftsman
who worked for the London Underground. He very much did it in his spare time
as a kind of pet project, and actually, not being commissioned
by the Underground at all. It was his own idea. It was something that he was, you know,
very passionate about. Beck was inspired by the circuit diagrams
he had to draw for work. He wanted to simplify the map. He wanted to design a map that didn't
emphasize geographical accuracies and distance like its predecessors. Beck redesigned the map so that rather
than being representational, with all the squiggles and wiggles
on the Underground line, he made sure
that it only represented straight lines, 45-degree and 90-degree angles. So it became like an electrical diagram. Much clearer
and much easier to understand. [Brosnan] Harry Beck took his map to the
publicity office at London Underground who were initially quite skeptical
as to his approach to the map. But after some persuasion,
they did initially try a trial at selected stations. The public loved it. All 500 disappeared,
and they got tons of positive feedback. [narrator]
Following the trial run's success, the Tube's directors commissioned
700,000 copies of Beck's map to be distributed. They were so popular that they had to print another
100,000 copies just a month later. So, it really speaks for just how
important simplicity is in design. [narrator] Beck received just over
50 dollars for his initial work, which is approximately 950 dollars
in today's money. Due to its overwhelming popularity, his design soon became the official map
for the London Underground. The wonderful thing
about Harry Beck's design is that it's survived
the difficulties of time as more lines have been put on the map. It's possible to accommodate it
using his very simple system. [Brosnan] The impact of Beck's map
was huge. Not just on London, but also graphically on other maps and
other subway systems across the world. [narrator]
By the middle of the 20th century, as populations grew and cities developed, countries all over the world were expanding their transport networks. Commercial travel, be it by rail, ferry or the increasingly popular airplane, was connecting people and places like never before. The notion that people can live somewhere
and work somewhere else. The idea that this is open to the masses
means that the connections we make, the size of our world,
the openness of our minds, is expanded. And so, inevitably,
we're able to progress and move further. [narrator] But little did the world know
that a new idea was in the pipeline that was going to join two landmasses
for the first time in history. [narrator] In the 1970s, the European continent underwent a transformation
with the establishment of the European Union, which Britain joined in 1973. [Wolmar]
Our links with Europe were growing. Our trade with Europe was growing. But also politically, you know, we were becoming
a greater part of Europe. [narrator] As Britain established itself
as a key member of the EU, the need for a transport link to get people across the English Channel
became a hot topic. Despite various ideas being put forward
over the past 200 years, no such link had ever come to fruition. So you've got these
two very important landmasses. You've got the UK,
and you've got mainland Europe. And yet, there's this annoying, narrow stretch of water
separating the two. And the only way to get across it
is either by plane or by slow ferry. There had to be a better way of doing it. [Wolmar] The trouble is
building a tunnel or a bridge between France and Great Britain is pretty difficult. It's very costly. We've had two world wars. And we've also had reluctance by the military to allow a tunnel, which they saw might have been used
by hostile forces. So all the early ideas were ditched. [narrator] But in 1986, after a number
of proposals had been submitted, the British and French governments agreed
to construct what would become known as the Eurotunnel, a 50-kilometer railway connecting
Kent in England to Coquelles in France. Once up and running, trains would be able
to travel at 300 kilometers an hour. But there was a problem. How do you convince the public
that traveling inside a high-speed train through a tunnel
75 meters below sea level is safe? We have billions of years of evolution
saying we shouldn't be doing this. We shouldn't be traveling this fast
in a confined space under water. You're meters
and meters under water, yet... Yet we are.
So we're kind of in this sort of polemic between we're wanting to progress
but just having these sort of genes that have been around
for billions of years going: "We shouldn't be traveling this fast
under water. This is just odd." [narrator] To allay any fears,
engineers put forward an idea. Rather than build two one-way tunnels, they would build an additional
service tunnel in the middle connected by cross passages. It would serve as an escape route
in the event of an emergency. [Papadopoulos] Human beings are amazing, because we anticipate
everything that can go wrong, and then we find ways
to stop that from happening. [narrator] In 1987, construction began. To cut through the chalk marl deep
beneath the seabed, workers operated gigantic motorized
tunnel boring machines. Modernized versions
of the tunneling shields used 100 years earlier
to build the London Underground. These machines also collected the debris, which was then transported along
conveyor belts and up to the surface. In total, 4.9 million cubic meters
of chalk was excavated. The newly-dug tunnels were then lined
with concrete to keep them waterproof. On December 1, 1990, construction workers
from England and France bored through the final section of rock, connecting the two countries
for the first time since the ice age separated them. [male newscaster] As the Champagne flowed in probably the biggest ever
underground party, the entente was very cordial. [narrator] Four years later,
the Eurotunnel was officially opened. [male train announcer]
Ladies and gentlemen, in a few minutes,
we will be entering the Channel Tunnel. [narrator] It's the longest
undersea tunnel in the world and is used on average
by 22 million people every year. The construction of the Channel Tunnel
was not only an amazing engineering feat, but also it has, to some extent, brought us closer together. [narrator] The opening of the Eurotunnel may have strengthened the connection
between Britain and mainland Europe, but in cities across the globe, as more people travel underground
every year, subway systems
are reaching breaking point. [narrator] Tokyo is home
to the world's busiest metro, with an average of three and a half
billion passengers using it annually. A number equal to almost half
the world's population. The city's main transport hub
is Shinjuku railway station. With over 200 platforms and an average
of 3.5 million daily passengers, it holds the Guinness World Record
for the busiest station in the world. So congested are some stations in Japan that subway staff have to literally
push passengers onto crowded carriages. But it's not just Japan
that's feeling the squeeze. Subway networks everywhere have become
a victim of their own success. Despite some metro systems
running trains during rush hour as often as every 100 seconds, overcrowding still persists. Many networks have set up 24/7, state-of-the-art monitoring systems to ensure the safety of passengers. Jam-packed platforms and carriages are a result of the same problem that was thwarting Victorian London
in the 1800s. A population invasion. In the past decade alone, the number of people
living in the capital has increased
by approximately one million, while a mega 30 million tourists
come to London every year, making it one of the most visited cities
on the planet. [indistinct Tube announcements] London's population has grown enormously. People tend no longer to be able
to drive into central London, because there's very restricted parking and there's so much congestion, so they take the Tube instead. And it's become just very overcrowded and congested. [narrator] To accommodate
for this increase, over the decades, the London Underground
has continually extended its network. But the city is still suffering. Nowhere can commuters feel this more than in the deep underground
Victorian tunnels during the sweltering summer months. The Tube tunnels are so small. And that really shows
the changes in our times, because there is no room
for air conditioning. And what's so fascinating about being
on the Tube is dealing with the heat. Heat from the brakes.
Heat from a lack of air conditioning. And you can really feel on those very hot,
sweaty days on the Tube that this is a very old, archaic system. [narrator] Unlike previous decades, extending the current Tube network
is no longer an option. [Wolmar] It is impossible to extend
London's existing Tube lines. They could not be widened, because that would be far too expensive
in terms of digging up the tunnels. You'd have to close them for many years. The platforms are not long enough to cope with extra carriages. [narrator]
So what's the congested capital to do? London is now undertaking
a grand tunneling project. And it's the largest engineering project
in Europe. [narrator]
In 2008, hearing the plight of Londoners, governing bodies for transport
in the capital agreed to build an entirely new line. Commonly known as Crossrail,
but officially named the Elizabeth Line after Queen Elizabeth II, it'll be deeper, bigger, faster and cooler than any line before it. [Wolmar] Crossrail is a quite amazing
engineering project, with ten new or extended stations
underneath London. With platforms that have platform doors. The whole system is air conditioned. The stations will be real cathedrals compared with the existing Tube stations. [narrator] Stretching over 100 kilometers and connecting the suburbs
of the west with those of the east, Crossrail will travel
through the heart of the capital. Once complete, each train
will be 200 meters long and will carry up to 1,500 passengers, almost double that of existing Tubes. As for the tunnels, giant boring machines
weighing 1,000 tons each have been used
to build the subterranean channels, which at 6.2 meters in diameter are almost twice the size
of existing Tube tunnels. What's more,
on some parts of the new line, passengers will be traveling
40 meters below the surface. That's 34 meters deeper
than the original Tube tunnels, which were dug
using the cut and cover method. Despite still being under construction, once fully operational, London's ultra-modern, brand-new railway line is expected to serve 200 million
passengers every year. The whole idea of Crossrail is completely
different from the early Tube lines. It's just on a much grander scale, and people will find it's a completely
different experience from traveling on the early, historic Tube lines. [narrator] London may have found the transport solution to its population growth. But what can engineers and entrepreneurs
in other parts of the world do to relieve
their ailing mass transit systems? [male voice] What you want
is to revolutionize the system. [narrator] Some innovators believe there's a way to increase speed
and capacity like never before. What if we got rid of wheels altogether? [narrator] But how do you
get rid of wheels on trains? It isn't rocket science,
but it was first imagined by one. In the early 1900s, physicist, inventor and the father
of modern rocket propulsion, Robert Goddard, envisioned a frictionless form of travel. Trains raised off their tracks by a process named magnetic levitation, now known as maglev. You've probably done the experiment
where you put two magnets together, and if you get them in the right way,
they repel one another. That's essentially
what you're using in a maglev train. You have magnets on the train, magnets in the track,
and that keeps it hovering above. [narrator] Over the years,
Goddard's idea grew in popularity. Supporters believe that if these trains could be made
into a mass transit reality, commuters in cities all over the world
could get from A to B a lot quicker, which could also lead
to increased capacity. The benefits of getting rid of wheels
is that you eliminate friction, because whenever two surfaces
rub together, that causes drag,
and it makes travel extremely inefficient. And so his idea
of using electromagnet repulsion meant that you're eliminating surfaces
that rub together, and so it's a much more
efficient way of traveling. [narrator]
When it comes to maglev technology, Japan and China
are already ahead of the game. The Shanghai Transrapid, which was built by German engineers, can travel at speeds
of up to 430 kilometers an hour, making it the fastest train in the world. While in Japan, developers are working on a train
to add to their existing maglev system, which, once complete, will be able
to whisk passengers across the country at 500 kilometers an hour. But with the need for speed
being the main goal, innovators believe
they can take the principles of maglev and go one step further
by reducing air resistance. One of the main obstacles
to any form of high-speed travel is the surrounding air, which causes friction,
and in turn, drag to slow it down. So how do you reduce air friction? You put the train in a tube
and decrease the air pressure. Enter Hyperloop. Hyperloop is about
taking all the benefits of maglev, but putting it in an evacuated tube. And because you're going through
this tube with very little air in it, you're pretty much eliminating
most of the drag or air resistance. That means you can get
up to much higher speeds. Essentially, it's a system of pods
that transports people within a tube. [narrator] Today,
companies all over the world are vying to make this concept a reality. From Hyperloop
transportation technologies to Elon Musk's SpaceX and Richard Branson's Virgin Group. Elon Musk described it
as a cross between Concorde, an air hockey table and a rail gun. [narrator] Passenger pod prototypes
and vacuum tubes are being trialed
at test facilities across the globe. If successful, the technology
could transport passengers at tremendous speeds. [Archer] Hyperloop could potentially get
up to speeds of 1,300 kilometers an hour. That's faster than planes, and it's even just a smidge faster
than the speed of sound. To put that into context, you could get
between LA and Las Vegas in just 30 minutes, which by plane
takes some two hours and 45 minutes. And what we're seeing today
with these modern Hyperloop structures being built above ground... It's almost taking us full circle back to the old elevated railways
we saw in the 19th century in New York. [narrator]
With projects gaining traction, Hyperloop could be operating
within two decades, paving the way for the next
revolutionary leap in mass transit. I'm very interested in seeing if this
takes off, if it is the way of the future. It's a pretty sci-fi concept. It would be
great if it works. But let's wait and see. I think these Hyperloops, as long
as technology allows, are inevitable, because there's not only
a lot of resource being put behind this, but I think there's a lot of will
in terms of being able to harness the amount of time that we have
on this earth and make the most of it. [narrator] In the past 200 years, thanks to the imagination
of our most brilliant minds, subway systems have continued to develop, turning elaborate concepts
into groundbreaking realities. These technologies
connect cities and towns, transform landscapes and above all, meet the demands of a thriving global population. If ideas like Hyperloop
are anything to go by, it seems there's no end in sight
for the future of mass transportation. [narrator] Imagine being unable
to cross this canyon or traverse this stretch of water
in a boat. Now we have the ultimate solution. [female voice] These are
an incredible feat of engineering that seemed to defy the forces of nature. [female voice 2] There's
two kilometers of road that's hanging with nothing underneath it. [narrator] This revolutionary design provides lifelines to rural communities and joins up great towns and cities, connects islands,
like Denmark's Great Belt Bridge, and links countries, like England and Wales's Severn Bridge. And even unites continents, like the Bosporus Bridge,
connecting Europe to Asia. [male voice] They're some of the
most beautiful structures in the world. They're iconic. [narrator]
To create these amazing structures, we have had to overcome immense engineering challenges and weathered failures to see them improve. So now they connect us, fuel our economies and oil the wheels of the developing world. [male voice 2] One bridge
makes a massive impact. The root cause of poverty
in those situations is broken. [narrator] These engineering marvels are suspension bridges. [high-octane music plays] [narrator] Bridges come in many forms. But the most typical are the beam, arch and suspension bridge. The UK's Severn Bridge is a glorious example
of the modern suspension bridge. A triumph of complex engineering in an elegant form. It's a beautiful looking bridge. It stands out from the rest, and it is quite unique. Always felt it would be nice
to work on such an iconic structure. And that's eventually
when I did see the advert. I took that opportunity to work on it, and I've been here ever since,
which is over 30-odd years. The Severn Bridge is a very simple, sleek,
beautiful looking structure. But it's very complex in its design. [narrator] But the roots
of this complex bridge lie in the deep, distant past. One of the oldest known bridges
is at the Sweet Track Causeway over bogs
in the Somerset Levels, England. Simple log bridges, originally constructed
by Neolithic farmers nearly 6,000 years ago. A beam bridge is perhaps the simplest
kind of bridge you can imagine. It's what happens
if you get something solid and then just plonk it straight over
whatever gap you're trying to bridge. [narrator] The principle
of the beam bridge is simple. Any weight compressing the center
is transferred to its edges where it is directed down
through the banks or supports. It's effective,
but only over short spans. The problem with the beam bridge
is you can only make them so long, and they can only carry so much weight. Ultimately, it depends
on the strength of the material that you're using to make that beam. Once something gets very, very long
and you put a large weight in the middle then slowly that force, the compression, is gonna just rip the material apart, the bridge will break,
and you'll end up crashing into the gorge. [narrator] The solution is to shorten
the span with central supports. The way you can get around it is effectively to make a load
of short beam bridges across whatever gap
you're trying to bridge. And that means you have to put
supports across that gap. [narrator] This solution can be seen
at Lake Pontchartrain in the American state of Louisiana. It is the world's longest
continuous bridge over water. More than 38 kilometers long. And uses
nine and a half thousand supports. The solution works in shallow water, but it's not so practical
for deep rivers or vast canyons. [Steele]
You might have to make tall supports if you're going over
something particularly high or you might have to build
in the middle of a flowing river, so all of this makes building the bridge
more difficult and more expensive. [narrator] 3,000 years ago, engineers in ancient Greece
improved the beam. This Arkadiko bridge,
in the Peloponnese, features an arch. The Romans developed the idea
a few centuries later and made glorious use
of the arch throughout the empire. Arched bridges are stronger
than beam bridges, spreading central load more effectively. Arches extend the maximum single span
of a beam bridge from 20 meters to 30. But beyond 30 meters, engineers still have to add
further supports. A bridge that could float, seemingly unsupported
across wide rivers or deep ravines, still seemed beyond us. But the solution had, in fact, been with us for millennia. [narrator] Rope bridges first appeared
near the Himalayas at least 4,000 years ago. A simple design, ropes are attached
to each side of a wide gap. Decking can be added to ease crossing. Unlike beam and arch bridges, the weight is transferred to the banks
by the tension pulling through the ropes. [Steele] Rope is something
that's really strong in tension, and this simple rope bridge
takes advantage of that tensile strength. It means that all the forces acting
on the rope are stretching it, pulling it. And that's how the rope
supports your weight. [narrator] Light and strong, rope can span longer distances
than heavier materials without supporting pillars. But they're not for the faint-hearted. [female voice 3] It moves around. So if someone's crossing ahead of you, it causes undulation on the back,
so the structure's moving up and down. And of course, when you have wind,
this also adds more movement. So the structure has a lot of movement
that needs to be designed out. [narrator] These unstable bridges
are okay for people. But not for heavy traffic, like army or trade vehicles. When it comes to trying to get
really heavy traffic across a bridge, like, you know,
a horse and a cart or a lorry, then a simple rope bridge isn't enough. [narrator] So the rope bridge,
cheap, strong and easy to build, was confined to small communities
with light traffic. While the developed world relied on
more sturdy beam and arch bridges to facilitate heavy traffic. It stayed that way
until the late 18th century, and by then, the need was pressing. Across grand European rivers,
like the Thames, piers effectively blocked large shipping, and small boats faced manmade rapids. London Bridge was for "wise men
to go over and fools to go under." [male voice 3] Bridge piers
tend to block part of the river, which means that the water
flowing through the spans tends to speed up. And like most things in a fluid flow, what we get is eddies. And we often get dangerous eddies
coming off of bridge piers. Shooting through there, you took
your life in your hands at certain tides simply because of the disruption
that multiple spans caused to the river. [narrator] With fewer piers, large shipping
could reach further upstream. [narrator] This was the solution:
the modern suspension bridge. The Severn Bridge
linking England and Wales illustrates the benefits. The Severn Bridge is designed so that
it gives you a clear shipping channel with a 47-meter headroom and enough width for large ships, rather than a multi-span structure,
which would have multi piers in the river, which could be an obstacle and a danger
to the structure if hit by shipping. [narrator] If the link across
this important shipping lane were blocked by piers every 30 meters, it would severely restrict shipping. The River Severn has got the second
highest tide and very fast currents. And therefore, you need
that space between the two towers to allow safe shipping access
to Sharpness Docks. [narrator] The secret
to the suspension bridge's ability to span far greater distances
than beam and arch bridges is also part of its elegance. It's only by traveling to the very top, a place where the public
are never allowed to go, that you can appreciate its true scale. [Phillips] You can see
from the scale how big the crossing is, and that clear span of 988 meters with glorious views in both directions. [narrator] But how does this bridge
manage to span such an enormous river? The breakthrough happened in America,
at the beginning of the 19th century. The inspiration came from merging two
of the most enduring bridge designs. [Boeree] So you've got
your conventional beam bridge, which, yes, that will span a gap
without a support, but is limited above a certain width. And then you've got your rope bridge,
which can span a larger gap, but is really, really wobbly,
so that's no good. So is there a way
that you can combine the two together? [narrator] The breakthrough came in. No image exists
of the genius behind the plan, James Finley, but there is a surviving sketch
of one of his early designs. Instantly recognizable, Finley designed a chimera, half beam, half rope bridge,
with the advantages of both. The real revolution in suspension bridges was when they realized
you could make the deck flat and rigid. And that meant that so much more heavier
traffic could travel across the bridge. And they became infinitely more useful. [narrator] The weight carried
by a beam bridge normally transmitted downwards
through piers is instead transmitted upwards
through suspension cables. [Arney] The flat deck
is supported all the way along. That distributes the weight
throughout the entire bridge. And it means that the forces are balanced
in a way that keeps it flat, keeps it up, and doesn't put too much pressure
on any single part of the bridge. The modern suspension bridge
is deceptively clever. You take a flat bridge, but instead
of supporting it at either end or from underneath,
you support it from above. [narrator] But the new design
wouldn't work unless the suspending cables were made of a material
capable of carrying the heavy loads. And that material wasn't available
until the end of the 18th century, when the falling price
of wrought iron in the US made the design affordable. The idea of using iron
to create super-strong chains came from the Chinese. [Somara] Initially they were using rope, but the Chinese came up with this idea
that if they heated iron ore, they could bend iron
into the shape of links, chain them together,
and you'd have a material that was able to take
a much greater weight. [narrator] Back in the 1430s,
a Tibetan saint named Thangtong Gyalpo built the first iron chain bridges. The bridges have since been replaced
with reconstructions, but they still use
some of the original chains. James Finley up-sized the Chinese design
to take advantage of cheap wrought iron. Each chain weighing over ten tons. His revolutionary design became the first
modern suspension bridge. The genius of the design
isn't immediately apparent. If Finley had simply attached his
suspension cables to bank side towers, the tension would have pulled them down. The towers seem like a great idea until you think about the forces
acting on them. If you had a tower on each bank, all the force,
all the tension from that chain is coming from the middle of that gap. And that means it's gonna be pulling
both of those towers inwards, and potentially
if they're not really, really solid, it's gonna cause them to collapse. So imagine instead of having that cable
just pulling on one side of the tower, you stretch it all the way over the top and bring it down to the bank
on the other side. [narrator] The suspending cables
are anchored beyond the towers, splitting the tension
between the ground and the bridge. That means you've actually
got tension acting in both directions, and that then means the tower...
the forces are balanced. It's not being pulled either way, and that means
it's stable and won't fall over. [narrator] The same principle
is still used today. In Chile these gigantic concrete anchors spread the strain over the towers. On the Cau Cau Bridge, we're using a mass anchorage, so it actually relies on its sheer weight. So we have a very large, 120-thousand ton concrete mass at the end rather than a small tunnel. [narrator] From the 19th century
to the largest structures of today, all suspension bridges
follow Finley's design. Allowing flat, rigid roadways,
which can carry modern traffic spanning vast distances. This modern suspension bridge
is critical to developed cities, but it's also of vital importance
to remote communities across the world. The need for suspension bridges
in rural communities where people are so isolated is acute. If you imagine living
in those kinds of environments, where you've got to walk miles
and miles to get to anything, a river, particularly a river that floods, is a major obstacle
to any kind of opportunity. And the result
is people remain in poverty. If you think about it
isolation means poverty, if you can't get to market
and you can't get to school, you can't improve yourself,
and others can't get to you. I've actually seen children holding their
schoolbooks above their heads and wading, holding their breath as they have to
get their head under the water to wade through the river
on the way to school. It enables others to get to the community,
not just the communities to get to places. But so other charities, other aid workers
can get to the people who need them. One bridge makes a massive impact. Huge change to the lives
and livelihoods of those people. And in fact to the economy as a whole. That tyranny of isolation, which is the cause, the root cause
of poverty in those situations is broken, so that now opportunity exists. [narrator] These modern bridges
now span rivers around the world. But the early bridges
were far from perfect, as a fatal tragedy demonstrated
in Great Yarmouth in England. It's 1845, and a huge crowd
of families and children have gathered to see a circus performer. The best place to view this performance
is on the bridge. And as they saw the performer traveling
down the river everyone rushed to one side of the bridge, which created an enormous force
on the chains. And unknown to anyone,
there was a weak link. That weak chain broke and caused a catastrophic failure
of the entire bridge. Seventy-nine people died,
many of them under the age of 13. And as the bridge collapsed, people
were crushed or thrown into the water. It was a heartbreaking tragedy, and it meant that suspension bridges
had to be rethought. There had to be a better way than this. [narrator] This tragic incident highlighted the limits
of the iron chain design. [Steele] A chain is only as strong
as its weakest link. It just takes a single one of those links
to be in some way not structurally sound, and then it can snap, and the whole chain has completely lost
all of its tensile strength. [narrator] It was clear that the iron
chain suspension needed an upgrade. Engineers searched for something stronger and lighter. The answer isn't immediately apparent
on the Severn Bridge, because it's encased
in a protective sheaf. But deep underground,
where the bridge is anchored, you can get a glimpse
of the modern solution. Inside their rust-proof
dehumidifying tent, you can see that the thick,
heavy iron chains have been replaced with thousands
of thin, super-light steel cables. [Phillips] We're now inside one of the
main cable anchorages on the Severn Bridge where we've got the main cable, which consists of 8,322 individual wires making up the bundle. This then splits up
into the small bundles, which are anchored around the shoes. [narrator] Like all modern bridges, the Severn Bridge benefits
from safety in numbers. With bundles of thin steel strands
acting like super strong rope. [Arney] Cables are strong under tension, and you can use several together, so if one snaps, there are others to take over. A failure is no longer catastrophic. [narrator] The use of cable
has made bridges safer, but bridge builders
faced many deadly challenges. Some from completely mysterious forces. [narrator] In America, the East River
separates Brooklyn and Manhattan. At points, it stretches
over a kilometer wide. For many centuries,
the only way to cross had been by ferry. In the 1860s, a new suspension bridge
promised to change all that: the Brooklyn Bridge. It was designed by a German immigrant,
John Augustus Roebling. Too wide for a single span, it was inevitable that one of the towers
had to be built in the river. Perhaps the single biggest problem
of working underwater
is that we can't breathe under water. So if all your construction
is being done by hand, then there's just no way that you can get
people down there digging up the riverbed
trying to put those foundations down. What you need to do is provide them
with a protective atmosphere that they can work in. And the way that this was done
is with a device called a caisson. [narrator] A caisson
is a large diving bell. It allows workers to breathe and keep setting concrete dry
under water. You can think about a caisson
like trying to push a cup down in the bath when it's upside down. It's full of air, and as you push it
underneath the water, that air stops the water from rushing in as a protective atmosphere
for your workers. [narrator] But as the caisson drops,
the pressure forces water into the bell. [Steele] In order to keep that water out, you have to apply more pressure
by pumping air into that caisson to make sure the water stays outside. And the only way to stop
the whole structure just crumpling is to make sure
that the pressure on the inside balances the pressure on the outside. So there's no force on the walls, and they can stay intact
and keep your people inside safe. [narrator]
The caisson makes construction possible, but it's quickly apparent
that something is wrong. The workers return to the surface unwell. Some even die. Is the air inside
the huge underwater casing poisonous? Or is there some deepwater virus? The mysterious illness
seemed to defy explanation. [Arney] Sending workers down
under the water had an effect on their bodies
that no one could have predicted, and no one really understood. [narrator] In fact,
it was a simple physics problem. At high pressures, more of the air
we breathe dissolves into the blood. This isn't immediately dangerous
until you return. [Arney] The problem isn't so much
working at high pressure for long periods of time. It's when you come to the surface
that the problems happen. That dissolved gas tries to expand
back into its gaseous form, and if it's still in your system, that can cause blockages
that could be fatal. [narrator] Today, caisson's disease is known as the bends, and is a constant danger for divers. But back in 1870s Brooklyn,
the phenomenon was little understood. As a result, the designer's own son, Chief Engineer
Washington Augustus Roebling, was permanently disabled by it,
and at least 21 men died. Tragically,
it was only after construction that scientists discovered how to prevent it from happening. When you go from
a highly pressurized environment to normal atmospheric pressure, it has to be done with time. Because that allows for any bubbles that
have formed in the blood to dissipate. [narrator] Decompression helped to save the lives
of future caisson workers and divers. Safety procedures were brought in
for later construction projects like the tunnels under the Hudson River
in the early 1900s. [male newscaster]
Let's join a crew of sand hogs as they start on the day's job
under the river. They must stay in the airlock
a few minutes, until the air pressure is built up
to equal that in which they will work. It is different
when they return from work. Then they must be gradually decompressed, which takes a much longer time. This whole process is for the protection of compressed air workers. [narrator]
But even with these precautions, the process is still dangerous. So these days, the risk is eradicated
by using technology to replace workers
to build underwater foundations. But the challenges
facing suspension bridge engineers are far from over. And it's not just how they're built,
but where they're built. [rumbling sound] [narrator] In 1906, an earthquake devastates San Francisco. Up to 3,000 people died, and over 80 percent
of the city is destroyed. The stone buildings can't withstand
the 7.9 magnitude shake. This disaster makes it essential
to earthquake-proof future building. Two decades later, San Francisco
plans to build the first bridge ever to cross the Golden Gate Strait, spanning over two kilometers. [upbeat jazzy music plays] [narrator] In the early 1930s, the city of San Francisco
is a major trade center. Yet it's isolated from the rest
of California to the north. Besides boats, they're cut off. But a suspension bridge
requires towers that would eclipse all the city's skyscrapers, reaching over 200 meters high. To make the strongest possible
suspension bridge, there's a very particular shape
of cable that you want to get to optimally distribute those forces. And what that means is that
as you make your span wider, you're gonna need to make
the towers taller to compensate, so you can keep your cable
in that special shape. [narrator] The stone towers
of the Brooklyn Bridge would no longer be suitable. They would be too tall. And stone would be particularly unstable
in an earthquake zone. A stone pillar,
as it gets taller and taller and taller... the mass of the stone will crush the stone below. So there is only a certain height
that you can go to. For the San Francisco
bridge's chief engineer, another German descendant,
Joseph Strauss, it was clear he needed
a completely different design. Once again, a breakthrough
in technology comes just in time. Advancements in metallurgy bring about
a new affordable material, steel. The mix of iron and carbon creates a strong but lightweight alloy far more flexible than stone. [male newscaster 2] Box girder towers
of massive strength carry the strain of huge cables
in many modern suspension bridges. [narrator] The new bridge
will span an earthquake zone, so it must be compliant, or, flex. [Wojcik] That is naturally compliant.
It will move. That movement is important. Allowing that movement
means that you cannot build up stresses within the material to the level at which that material
will then subsequently fail. [narrator] When subjected
to the forces of nature, materials need to absorb them
and allow the energy to pass through. Compliance prevents materials
from getting damaged under stress. If you think about a blade of grass
in a gust of wind, it will give. It doesn't permanently give.
The grass will spring back into place. You haven't broken the grass
by blowing the wind across it. It's just kind of allowed the wind
to blow over it. So if we compare, let's say an oak tree and you have a gust of wind, then that structure can't comply. And as a consequence as the force
of the wind pushes up against the tree, all of that force
has no way of being relived. And as a consequence of that, could exceed the actual tensile strength
of the tree itself. And the tree could snap, literally snap. [narrator] And so in 1933,
construction begins. And the iconic steel towers of the Golden Gate Bridge rise up. Instead of creating a heavy, solid tower, the steel creates
a honeycomb lattice structure, which is lighter but still strong enough that each tower
can support a 60,000 ton load. Although this bridge was designed
to be safer, construction comes with a human cost. Working at these heights is extremely dangerous, and 11 men lose their lives. But the death toll
could have been much higher. Incredibly, 19 other people were saved when they were caught
by nets as they fell. This was also the first bridge to insist on workers wearing hard hats
and safety lines. It was a big step towards the greater protection
that construction workers enjoy today. At the same time, an almost identical steel design
to the Golden Gate is used for the Oakland Bay Bridge,
just around the corner. The bridges stand proud for decades until they are finally put
to the ultimate test in 1989. [dramatic music plays] [sirens and screaming] [narrator] The earthquake causes
heavy damage across the Bay Area, though less severe than 1906. It causes six billion dollars of damage
and kills 63 people. Roads and bridge decks collapse. But not the suspension bridges
across the Golden Gate or the Oakland Bay. [Collings] The West Bay Bridge,
which is the suspension bridge, nothing happened. The suspension bridge
is very good in earthquakes. Very little happens to it. [narrator] The 1930s design
was so effective that the suspension bridges
still stand strong today. But earthquakes are not the only natural force engineers have to overcome. They face a problem
related to rope bridge ancestry. [narrator] As decks get longer,
they become more vulnerable to a phenomenon all too familiar
to the original suspension bridges. Swaying, sometimes with dramatic results. Three years
after the Golden Gate's construction, the Tacoma Narrows Bridge in Washington is opened in 1940. This bridge was designed
to safely withstand 225 kilometer per hour gales. What happened next
should have been impossible. The result of a comparative
65 kilometer per hour breeze. An amateur cameraman
captures this incredible footage as the center of the 11,000 ton span twists like a ribbon in the wind. The oscillations become life threatening
and the bridge is evacuated. But one man stays. His dog is trapped in his car,
and he doesn't want to leave it. Despite the dangers,
there's little sign of panic as no one seems to recognize
the stress the bridge is under. The man decides he has to leave
his dog in the car for now. The twisting weakens the bridge until it can take no more. [Arney] It's incredible
that no human lives were lost when this bridge collapsed.
But it was so close. Imagine if this bridge had been full
of commuters early in the morning. Dozens and dozens of cars. They could all
have been thrown off into the river. It could have been
an enormous human tragedy. [narrator] No one understands
how it happened. [Arney] This bridge was designed to
withstand high winds and air turbulence. But the incident happened
at a relatively low wind speed. So the engineers had a challenge. They didn't know what they'd done wrong. Why would this bridge collapse when it should have
withstood those forces... easily? [narrator] Had scientists
got their calculations wrong? The Tacoma Narrows disaster sent shock
waves through the engineering community. Was this a fundamental design flaw
in suspension bridges? And did it affect
all other bridges around the world? [Boeree] Any person
who'd ever built a suspension bridge was sitting there thinking: "Well, damn,
is this gonna happen to my bridge?" And as a result,
building of all suspension bridges was put on hold for nearly a decade. [narrator] The pressure was on
to explain the seemingly inexplicable. [Wojcik] The situation is rather complex, and for many years, there was some argument
as to what caused the bridge collapse and how in fact it did collapse. Most experts now agree that Tacoma Narrows failed as a consequence
of aeroelastic flutter. Flutter is something that all
aerodynamicists are very worried about. You build an airplane, and then it's tested against this form of oscillation movement. [narrator]
Flutter is a dangerous instability caused by air flow over the deck. [Boeree] Basically what happens is, as a sustained wind
is blowing from one particular direction, it starts creating these air currents, these sort of vortices and eddies
on the leeward side of the bridge, on the side
where the wind is passing over to. And over time, these vortices start
getting underneath and over the bridge and starting to sort of
make it swirl a little bit like this, and the more it does it,
the more these forces grow, and it starts getting stronger
and stronger until this motion
is unbelievably exaggerated. [narrator] As the eddies push and pull
at the bridge, they strengthen. If the timing of the swing
matches the bridge's resonant frequency, the structure oscillates violently. Everything has a natural resonant
frequency. So that's a frequency
at which you can wobble it, and that wobble will continue to amplify. [narrator] Under specific conditions,
the movements build upon each other. [Boeree] So what the wind was
kind of doing was, it was behaving like, you know, an adult
pushing their kid on a swing. [Boeree] It kept applying a little bit
more force at just the right time to get it going until it was getting
really, really out of control. [narrator] The bridge hadn't been
designed to resist this vertical flutter. [Steele] The engineers had considered
the horizontal force of the wind trying to push the bridge over, but they hadn't considered
the vertical forces, things like the lift, which pushes it into the air. And because of those additional forces,
it meant the bridge was being pushed up and down, up and down, to the point where it could get
into this resonant groove until it amplified and amplified,
and the bridge collapsed. [narrator] How could they engineer
the structure to prevent the eddies from forming? It wasn't until the 1960s
that they found the answer. For decades,
there had been an oppressing need to build a bridge
across the River Severn. A road bridge that wouldn't just connect
two cities, but two nations: England and Wales. [triumphant music plays] [narrator] Cars going from Bristol
to Cardiff had to cross by ferry. The Severn Bridge became the first bridge designed to overcome
the oscillation problem. The engineers had a radical solution. For inspiration,
they had looked to the sky. Designers realized that instead
of fighting the wind, they could use it. [Boeree] Plane wings have
an interesting sort of fact about them in that they're shaped in order to provide lift. And the problem that they had
with bridges and wind is that they wanted the opposite: They wanted a
downward force to keep the bridge stable. So what do they do? They just copied
the design of aircraft wing but turned it upside down. [narrator] Structural engineer
Bill Brown's design turned the bridge deck
into an inverted plane wing, called a box girder. The deck is aerodynamically shaped
to create stabilizing air pressure. So basically the bottom side
of the bridge would have a curve while the top of it would be flat. And this lowered air pressure down here would mean that the bridge would have
a downward force acting upon it. [narrator] The box girder decks
are hollow, allowing interior access for maintenance and an exclusive glimpse
inside the labyrinth of tunnels directly underneath the bridge. This is a typical bay
in the box girder bridge with an aerodynamic shape. It's very lightweight steel. It's ship building construction
with very thin plate with stiffening. The Severn Bridge was the first bridge
to use this aerodynamic shape. From there, everybody is using this
for their suspension bridges. [narrator] The bridge's bold innovation
was world-changing, stabilizing long span bridges. [Boeree] This solution was the
breakthrough engineers were looking for. It was a leap forward
in terms of suspension bridge design and enabled them to build bridges
spanning gaps previously thought impossible. [narrator] The Severn Bridge
set the standard, but the challenge is greater
in typhoon regions. [Firth] When you're building bridges
in places like Hong Kong, China, South China Sea, typhoons, of course,
are a major design parameter. You've got to be dealing
with some very, very strong winds. [narrator] To survive typhoons, the Shenzhong Link in China has made use
of a clever twist on the old design. In high winds, the traditional box girder
can't always stabilize the deck. [Firth] The wind impacting
those incline surfaces may actually have the opposite effect,
to push it up. So it's quite a complicated design
exercise when you're doing this, to get that balance right so that the lift forces
are carefully controlled. [narrator] The solution for this
is to split the box girder deck into two parallel decks
with a space between them. The gap reduces the impact of the wind. [Firth] There's an air gap
down the middle. What that air gap does
is it equalizers the pressure or helps to equalize the pressure
top and bottom, so that you don't have
such big dynamic forces to deal with. [narrator] But more radical
is the positioning of the main suspension cables. Instead of running parallel
either side of the deck, they run down the center
of the deck above the gap. The cables start out at the top
of the towers on the center line. But as they come down
to the bridge deck, they splay out and they pick up the deck on the outside, go at a sort of triangulated cable system. So when the wind blows, the bridge deck,
when it tries to move sideways, is more resisted, the movement
is more resisted by this arrangement. So the Shenzhong Link
is designed very much with the aerodynamic
and the wind load situations in mind. [narrator] Despite all the advantages
of steel suspension bridges, they have an Achilles heel. It's mother nature's ultimate corrosive
challenge to engineers. [narrator] Rust.
An insidious creeping problem suffered most in humid areas, particularly near the sea. To try to prevent rust,
bridge builders paint the metal, but water can get under the paint
and destroy the structure from within. [Wojcik] It has this terrible tendency
to corrode. And there's very little
we can do about that. It's nature having its own way. [narrator] It's critical
to spot this corrosion before it becomes dangerous. But this is no mean feat. [Collings] Suspension bridges
are very large structures. They have towers that are high in the air.
They have cables that are high, usually over the sea or a river. And often, it's windy and it's rainy. It's a very difficult thing to access, but inspection is a very difficult and really quite a dangerous activity. [narrator]
So incredible, gravity-defying robots have been designed,
which can cover every inch of bridges above and below. Maintenance robots
aren't just looking for corrosion, they can also spot signs
of otherwise hidden damage to the bridge. In the past, bridges have collapsed
because of weaknesses in the structure. Future technology may prevent collapses
and help us have the confidence to build bigger
and more ambitious suspension bridges. Perhaps the most innovative design
is by engineers from Norway, which would take suspension bridges
to the next level. Norway is a country
that's dominated by waterways. And there is constantly
this engineering conundrum of trying to join up islands. And rather than using
the conventional technique of drilling foundations down
into the fjords, which would be a really difficult task, they've come up with a much more novel way
of creating bridges. [narrator] Instead of sinking deep legs
for the towers, they are inspired by an industry
that is no stranger to deep sea construction. These oil rigs have no solid foundations. Instead, they float. It's almost a sense
of repurposing engineering. Floating oil rigs have been successful, and now Norway is using that concept to be able to create
floating suspension bridges. [narrator] If they make the base
of the towers sufficiently buoyant, they can support themselves and the weight
of the multi-thousand ton bridge deck. [Boeree] And it's kind of elegant that,
actually, in the end, the way to span a bridge of water
is to end up floating on it. [narrator] But there's a catch. [Boeree] If you have a floating tower, now, that brings up the old problem
of instability, because you don't want your bridge
to be able to start rocking and moving or going with the tide. [narrator] The solution
is in precise anchoring. [Firth] You have tension cables, which are
anchored into the bottom of the fjord, and you then pull this thing down,
so it's just below the surface, so that you've got this buoyancy force,
which is trying to lift it. It's trying to float, but it's held down. And that becomes a platform
just below the surface of the water on which you can build your bridge. [narrator] Just like oil rigs, as long as the anchoring cables
are tight and secure, the floating structure will hold steady,
even in heavy weather. But if the anchors were to fail, the repercussions would be serious. To work, these bracing tethers would have
to perfectly balance competing forces to ensure stability
without too much flexibility. Extraordinary technology, very
complicated, very difficult to deal with, and of course it's still in its infancy. But what it does is it suddenly
opens up the possibility to be able to build bridges
across places that we hitherto have just not even been able
to conceive of doing because the water's just too deep. So we'll see where it goes, but I think floating suspension bridges
are a really exciting development. [narrator] Suspension bridges
have a bright future and will continue to push the limits
of engineering. Since the modern suspension bridge
was invented, their span has roughly doubled
every 50 years. So I'm so excited to see just how wide of a gap we can bridge
one day with a suspension bridge. [Boeree] Who knows,
one day we might be able to do away with the majority of boats, because actually
we can connect most islands to each other or to the mainland,
just by beautiful suspension bridges. [narrator] But not all bridges
will be so complicated. There's still a need for cheap,
simple bridges. Though these may well
be delivered with a twist of the high tech. And now more than ever,
suspension bridges can unite communities and enable people to thrive in both cities and remote regions alike. Boasting iconic designs, which have evolved to span further, carry more and survive earthquakes,
tornadoes and corrosion. And admirers will continue to celebrate their scale and majesty in every kind of way. [narrator] This is the center
of the global economy, a transshipment hub for goods: From mobile phones to bananas
to the clothes we wear. We got to experience products
that would have never reached us. [narrator] On a daily basis,
millions of tons are shipped across the oceans. And millions of tourists
reach every corner of the globe. The extent to which
great technological inventions transformed this spot
is all but unparalleled: It once inspired yearning;
it was the gateway to the world. It was people from different communities,
from different countries, connecting, speaking this was
sort of very, very important. [narrator] Today it brings
the world home to us – and this at breathtaking speed. The technology involved in making
that smooth and quick and efficient is mind-blowing. [narrator] For the longest time,
muscle power was very much in demand here. What counts today
is technological know-how. Having something that could just go
...and then stuck it up. ...must save a lot of time. [narrator] Automation has made
people’s work easier and, at the same time,
it has made them obsolete. The question would be
where are all the people? [narrator] It has dramatically
changed our view of the world, the way we travel
and the way we consume. It was, is, and will remain the impulse
generator for our future: the port. [theme music] [dynamic music] Rotterdam.
About 30.000 ocean-going vessels, including gigantic container ships
like the Marstal Maersk, call to port here year for year. Some 60 meters wide and 400 meters long,
it is among the world’s largest vessels. Its cargo: almost 20.000 containers. At the port, the clock is now ticking.
Time is money here – a lot of money. Man and machine toil away. In the global rankings however,
the Port of Rotterdam only came in 11th. The competition is getting tougher. Our customers
always want the lowest price, which forces us
to be as efficient as possible. to actually be able
to offer competitive prices. They want the vessels in and out. Our productivity must be
as high as possible. We have to work
as effectively as possible. [narrator] A global problem
that logistics is trying to address with cutting edge software. Every minute, ten thousands of containers
need to be distributed. The ship is off
and on-loaded simultaneously. [calm music] To avoid lengthy
and expensive re-stacking, ship planners meticulously organize
the processes on their computer. Color-coded boxes
are moved virtually and allocated to
the appropriate warehouses. We see where the container is from,
what size and weight it is and where it is to be discharged. It is either discharged here
or in Asia or South America. We prepare the plans
on our computer system so our counterparts on the outside
can continue working with it. [narrator] The competition is stiff. If ports don’t meet
their customers’ needs, ship owners will simply
call at a different port. What's at stake today
is time and efficiency and cost. We are dominated by
price wars more than we think. Two-thirds of all goods are shipped by Sea
because it's cheapest ways of transporting goods
and so our waterways are oceans and seas are filled with containers that are shipping goods
all over the world. [narrator] The history of ports
and maritime trade is inextricably linked with the cultural history of humankind. Man has always endeavored
to transport goods across the ocean. [adventurous music] The first trade ship
goes back to the Phoenicians. As early as in the third millennium
the first artificial ports were constructed. [adventurous music] They went on extended
mercantile expeditions during which they founded
numerous colonies in Southern Europe. Apparently, the City of Málaga
was also founded by Phonoecians. During the Middle Ages,
maritime trade greatly influenced the development of cities. Hanseatic merchants in Northern Europe
joined together as a confederation. This so-called "Hanseatic League"
encompassed up to 300 seaside and inland towns. Most of the towns
were located in an area that would today reach
from the Netherlands to the Baltic states
and from Sweden to Central Germany. [adventurous music] In the 16th century, from this base,
the Hanseatic traders created a sphere of influence
that would span most of today’s Europe. The economic success
of the league was primarily owing to their powerful fleet
of trade ships known as "cogs". [adventurous music] The Hanseatic League was regulating
the trade between cities in the Northwest and Northeast of Europe
so we had things like copper and other metals from Sweden,
skins and furs from Russia, wine and other nice things
from the Rhineland. It sort of resulted very affluent
for the time cities popping up on the coast of northern, Europe. [narrator] Hong Kong’s
international reputation as one of the most important commercial
centers is also down to its harbor. Victoria Harbor was crucially important
for Hong Kong’s development. Apparently this is also why Hong Kong
was claimed as a Crown Colony by Britain in 1843. Hong Kong harbor is a natural harbor
lying in the South China Sea between the Hongkong Islands
and the Kowloon Peninsula. British merchants quickly recognized
the harbor’s potential for their trade fleet. It offers everything you’d expect
from a natural harbor: A deep-water bay that is protected from
strong waves and furnishes safe anchorage. [nostalgic music] The foreground features a natural,
beautiful harbor where large vessels and the soldiers look like play ships
in a children’s bath. Behind it are the Chinese mountains. Thanks to its strategic location
in close proximity to the Chinese mainland,
the harbor quickly evolved into a center for trade with East Asia. Victoria Harbor in Hong Kong
was tremendously important, especially for many colonies.
The Brits traded there. [narrator] Victoria Harbor soon
emerged as one of Asia’s premier ports. Up until the 1970s, many shipyards
and trading companies settled here. Hong Kong had become an important
outpost of the British Empire. In Hong Kong, the decisive impulse for
the city’s development came from the port. To this day, Hong Kong is one of the most
important economic centers of the world. It’s telling, indeed,
the idea is to demonstrate strength. Controlling a harbor is tantamount
to controlling a gateway – and thus deciding
what enters and leaves. It’s not just about transport
– it’s also about politics, sociology and ideology. [narrator] The way in which harbors
were built in their day can clearly be seen in La Rochelle,
the port city in Southern France. During the Middle Ages
the old harbor of La Rochelle was transformed by Templars
into the Atlantic coast’s biggest port. Often harbors
also served as fortifications. They offered protection
for the towns behind them. Two ancient defense towers
secured the port entrance. During the late Middle Ages,
a heavy iron chain was stretched between the towers
to block entry for sailboats. Today the Old Harbor of La Rochelle
is a tourist attraction. -[screeching seagulls]
-[people talking] [cheerful piano music] In the industrial age
it was mainly workers and seafarers who put their stamp on old port towns. They developed into spots
with a very particular charm. Ports were the gateway to the world. Not just for sailors
but also for travelers. [relaxed jazz music] Interestingly, harbors weren’t conceived
just to transport things from A to B. It was more about forging connections,
bargaining and things like that. The idea was to bring together
different people from various communities and countries.
That was very important. [narrator] Usually the port was
a region’s largest employer. People settled close-by. And the seaport-typical pubs
and drinking holes took hold. So as sort of the rules of economics
and supply and demand tend to dictate, typically speaking where you have areas,
where men are coming back from being out at sea with
just the men and they come back to land, they probably have various wants and needs
that have not been fulfilled and there are usually plenty of women
looking for work and so I guess prostitution
and red light districts were sort of a very unsurprising
results of a port city. [relaxed music] [narrator] It was in harbors
where famous maritime explorers started their daring expeditions,
which completely changed the world view of that time. It was called the age of Discovery
when we were sending all these ships around the world and starting to discover
things like the Americas with Columbus. And even first person to sail all the way
around the world that massively shapes how we saw the world
that we saw it as a globe, it is a globe, flat-earthers,
and really made us define what the continents are and see
the bigger picture and it's fascinating. [narrator] Vasco da Gama
was the first to prove that India can be reached by sea. For the longest time,
it was believed that the Indian Ocean was an inland sea
and that there was no connection between the Atlantic and Indian Oceans. But on the 8th of July 1497,
da Gama set sail from Lisbon. He steers his fleet eastward
– through the Atlantic and circumnavigates the stormy Cape of
Good Hope at the southern tip of Africa. Sailing along the East African coastline,
he finally reaches the Indian Ocean and the port town of Calicut
– after ten months at sea. The sea route to India
had been discovered. The numerous expeditions and
seaborne trade demanded new sea routes. Like the Suez Canal, for example,
which is part of the maritime Silk Road, and forms the boundary
between Africa and Asia. [exciting music] Until the 19th century,
ships from Europe had to sail around the entire African continent
to reach India and the Far East. The dream of building a canal
that connects the Mediterranean with the Red Sea
– and thereby dramatically shortening this journey –
has been around for ages: Long before the ancient Egyptians
tried to conquer the desert. But the construction of a waterway failed;
the canal silted up. Nor was this ambitious project
realized under Napoleon. His surveyors,
after making some miscalculations, deemed the project unfeasible: The handy thing about the Suez Canal
say compared to something like the Panama Canal is
that the Red sea and the Mediterranean are at almost identical level
and so that means that you could sort of digger a channel between the two
and you don’t have to worry about strong current going
from one to the other so it didn't require
locks or anything else. [narrator] The elaborate construction work
didn’t get underway until 1859. French engineer, Ferdinand de Lesseps,
took up the initiative to build the canal. It was the biggest
construction project of its time: in the middle of the desert
and far from any kind of infrastructure. [driving music] The construction of the Suez Canal
it was an absolutely huge undertaking. Early on actually,
they're using a lot of forced labor, they had a problem delivering water
to all of the workers. They had something like
1500 camels trying to do that. They did try and improve the situation.
It wasn't great but thousands I thought to have died and in particular
a number of cholera outbreaks that were causing some of these deaths.
It was not a great undertaking. [narrator] After ten years
of construction, the canal was opened in 1869. [tense music] Despite the sad circumstances,
Ferdinand de Lesseps had achieved a masterful feat in the barren desert. An invaluable shipping short cut amounting
to 7000 km between East and West. To this day, the Suez Canal is considered
the world’s most important water corridor. Thanks to this shortcut,
the number of ships traveling the seas kept climbing. Up until the mid-19th century,
they were carried over the oceans by sail. An invention then led to
a dramatic change in ships themselves: [exciting music] The Invention of steam-powered ships
massively opens the world to more ships and navigation. Because, think back to the sail ships
and you're heavily dependent on the wind’s direction as to
whether you can actually go. So that eliminated that factor.
You were able to go anywhere you wanted, whenever you want it.
That really just opened the floodgates. [narrator] The advantage was
that steam engines delivered constant power for the journey. This made it possible
to calculate reliable shipping times. [exciting music] Steamboats revolutionized the world market
because now the time constraint of transporting goods
was less of an issue, which meant that we got
to experience products that would never reached us in the time
that it takes to cross the seas. Steam engines are obviously
a big step forward in terms of energy efficiency because
they ran off coal that is a very energy dense fuel source
as opposed to something like wood. But the trouble with steam engines is
that they take up a lot of space. So the coal that they require to run off,
that takes up even more space and together that would take up
almost a third of a ship's cargo hold. [narrator] Since steam ships
also served as emigrant ships, this lack of space
didn’t just affect goods. Up to the late 19th century
it was primarily Europeans who left their homes
in search of a new life in America. Conditions aboard the ships
were still very cramped in the beginning. But the steam ships
heralded a new era here too. They enabled passengers to cross
the Atlantic in just 20 days or so. This made transport cheaper
and more affordable for wider sections of the population. [calm and cheerful music] [steamer horn] At the beginning of the 19th century,
large passenger ships were still used primarily as a means of transportation.
But since it wasn’t possible to book a passage for the winter months,
they accrued losses for the shipping lines. Albert Ballin, a Hamburg-based ship owner,
came up with the groundbreaking idea of using the ships
for pleasure cruises in warmer climes. In 1891, he dispatched
the Augusta Victoria to the Mediterranean with 241 passengers.
This was the beginning of cruise trips. Up to the mid-1930s, luxury cruises
became increasingly popular. Larger and faster ships were built
to accommodate more and more passengers. Freight ships also grew in size.
And the huge increase in goods necessitated more dock workers at
the ports to load and unload these goods. These so-called "stevedores"
tried to distribute the ship cargo as quickly as possible. Occasionally, however,
the cargo had spoiled during the journey. There were some wonderful advancements
that came out of necessity. People realized that they could transport
just about anything relatively quickly. But of course, when it comes
to fresh fruit and vegetables, quick is never really quick enough. They only last a few days,
and that's until we see the refrigeration of compartments. At the time, you have to remember
that this would have been heralded as a huge victory in terms of
human and commercial progress. [narrator] With the invention
of refrigerated vessels, now even perishable goods
such as bananas or meat could be transported. The luxury goods of the time
finally became available to everyone. [eerie sounds] But there’s one invention
that would revolutionize the port – and the entire
global economy along with it. Prior to this invention,
goods were still unloaded piece by piece. A time-consuming undertaking. They have unloaded goods
almost individually and that was a problem
depending on weather conditions right. You know if it's raining snowing windy
then you could damage the item. So they actually kind of
had to hold everything at the port and they wouldn't be able to do anything. They would be sitting around
waiting for the sun to come out. That's nuts. [narrator] Loading and unloading
was connected with long waiting times in general. Exactly this is what
he wanted to change in 1856: American freight forwarder Malcom McLean: [harp and guitar music] There is this guy Malcom McLean
who started out as a truck driver, but as he was going about
his shipping business, he realized it was really inefficient
to always drive up with a truck open it up, empty all the goods
out on individual pallets, then reload them into another truck. He was like why don't we
just detach the whole thing stick that on the boat and then
put that onto a new truck? [narrator] McLean evolved
his mobile truck-trailer idea. Loading the entire
truck-trailer along with the chassis onto a ship was inefficient.
There had to be a simpler method: What if we had a standardized
shape of box or container? Then you just move it off a ship
and onto a truck and load it
wherever you need it to go. This seems genius now, but at the time,
people thought it wouldn't make any sense. Why would you do that?
But he, like most people who actually end up succeeding in
business, sticks to his idea. He has that grid
and believes what he's doing. He can't get funding.
He can't get a loan. So he sells up all of his business,
whatever he was doing at the time and invests all the money by himself
into developing a container. [narrator] He also had a navy tanker
converted into a container ship and sent it from Newark to Texas
with 58 containers aboard. The steel boxes attracted attention
– and copycats. McLean had created a standardized box. To this day, it has the same
exact dimensions all over the world: A standard container measures 20 feet
– approximately 6 meters. The so-called "Twenty Foot
Equivalent Unit" is abbreviated as "TEU". It’s the same shape and size
that we use today. The container fits perfectly on a truck. It can be hoisted onto it
and subsequently off-loaded. This completely changed shipping. Standardizing the boxes changed everything
because loading and unloading became a much more simple process. As a result, everything got more efficient
and less costly. The downside of that was
the labor intensity decreased which is often the case with technology. [narrator] Before containers
were introduced, work at the docks was very strenuous. Heavy goods were off-loaded from ships
and transported to warehouses using sack barrows. Technological advances along with
the advent of the container dramatically changed working conditions. Goods no longer needed to be taken
to a warehouse since the container itself
functioned as a mobile storage shed. [calm music] It also was more secure as well,
because it meant you can put a completely sealed container
and know that you now keep it locked the entire time and try not to worry
about the ships’ crew getting into and drinking whatever it contains,
if it contains liquor, so it's a really cool idea. [60s music] [narrator] But it would take
until the late 60s for the first container ships to reach
the ports and usher in a new era. [60s music] Ports needed to adapt to new requirements
that went hand in hand with containers. Modern gantry cranes
were installed on the quays. The old, small-scale port facilities
were no longer suited for container transshipment. What was needed now was large,
contained areas to stack the shipping containers. And, above all, the role of technology
took on ever increasing importance. All the operating procedures
and all the container movements are monitored by an EDP center
from which shipping companies can always get the latest information. And an entirely new type
of ship was developed. The so-called "container ships"
not only had a different shape, they also had larger loading hatches
than the previous bulk freighters. In the 60s, ships pulled out of port
with 500 containers. In the meantime,
their capacity has grown rapidly. Especially over the past 15 years,
their loading capacity has skyrocketed to the extent that
a "new biggest" ship is launched somewhere
in the world every year. Today these floating heavy-weights
are more than 60 meters wide and 400 meters long. And there’s no end in sight
to this development. With the introduction
of shipping containers what you're seeing is
the development of an economy of scale with the port industry
and with the shipping industry. The more stuff you're able to send
in mass the cheaper everything gets. The labour goes down
the cost per item goes down. It just makes everything more efficient. [spheric sounds] [narrator] These ever bigger ships
have become a real challenge for ports. The greater their draught and width,
the more difficult it becomes to maneuver these "super ships". Controlling ship traffic is a complex job. Without the navigators in
the Vessel Traffic Service Center, ports would be paralyzed. Great ship widths pose a challenge
but the real issue is often the ship’s draught. Many ports aren’t deep enough
to accommodate very large vessels. Various restrictions apply
for unusually large vessels. A traffic separation scheme is in place
to avoid the risk of collision. And we coordinate vessel traffic
to ensure that approaching vessels can do so efficiently,
safely and smoothly. [narrator] The OOCL France
with its 366 meters in length is among the very large container ships. Navigating a vessel this size
is a real challenge for maritime pilots. [tense music] Anything 340 meters or longer
– or 46 meters wide – requires two pilots. One person alone
can’t keep an eye on everything. On this ship, for example,
there are 120 meters in front of me but I also have 240m behind me. If I pass a small vessel,
I have to go outside, look down and see if I can pass safely. While I’m doing that
I can’t properly focus on my piloting duties
because I’m located at the ship’s side when actually I should be in the middle
in order to pilot the ship. [narrator] A mega vessel
can only be guided into an inland port safely and smoothly
with the help of local tug captains who know the water’s vagaries. So, despite all the advances made,
the responsibility of pilots has actually grown. The expanding tonnage of vessels
has changed our profession and increased our scope of responsibility. Pilots used to just direct
the course of one small vessel. These mega vessels
– whether container ships or passenger ships –
really strain the dimensions of many ports. Keeping a comprehensive overview
of everything is absolutely crucial. [narrator] When it comes to passenger
ships, too, the shipping companies are always vying to out-do
one another with the "biggest", "fastest" or "most luxurious" ship. The cruise ship boom
has been going on since the 70s. During this time,
not only have the ships become bigger, everything about them has changed. Cruise ships look
more and more like small towns. In addition to room and board,
they offer a wide range of leisure activities. Sea cruises are a new branch
of the tourism industry; leading to bigger and bigger ocean liners. They can be 360 meters in length
and carry almost 7000 passengers. This incredible growth
entails consequences: Cities are completely overwhelmed
with the surge of tourists. More than 600 cruise ships
with 1.5 million tourists on board moor in Venice every year. Thus far, the giant passenger ships
have been able to pull right up to the dock to give their guests
a magnificent view of the sights. But environmentalists,
and those trying to preserve local cultures and traditions,
fear for the delicate ecological balance in the lagoon. In the meantime, the city has reacted. Since 2019, cruise ships have been banned
from the historical center of Venice. It's the same with container ships. They too have become so big that many
harbors can no longer accommodate them. Cruise ship operators from all over are
advocating waterway development programs. But they are facing resistance
from nature conservation organizations that fear serious consequences
for the ecosystem. Often enough, however,
commercial interests are able to override
environmental concerns. Many things need to be taken
into consideration before dredging shipping channels
to enable accommodation of larger vessels. To prevent the current and the water level
from changing, for example, the excavated soil must be
deposited at another spot. The river is also being widened. Works like this
in the end add up to several million euro. Fairway adjustment is fairly common. The Panama Canal being
the most prominent example. The Panama Canal too had reached
its capacity by the late 20th century. It was neither wide nor deep enough
for the colossal new ships. The canal was built at the end of the
19th century and inaugurated in 1914. At this time,
no one could have envisioned today’s mega-sized cruise ships
and super tankers. [mysterious music] The 82-kilometer-long Panama Canal is one
of the world’s most important waterways. It links the Atlantic and Pacific Oceans. This direct route lets ships
bypass the treacherous Cape Horn or the Straits of Magellan
at the southern tip of South America. The Panama Canal
was really big for world trade. This is allowing you to easily access
between the Atlantic and the Pacific so this was great for the trade. It was also great for Panama itself,
because they could charge people to go through
and they made lots of money that way. [narrator] Before the extension Panama
collected a billion dollars per year from ships that transit the canal. This makes the canal Panama’s
most important source of income. And also the reason
why it had to adapt to the new ships. So some one-hundred years
after the big opening, this canal too needed to be expanded
– and have new locks installed – to be able to keep up
with the growing volume of ships. Since 2016, ships with
a freight container volume of up to 14 000 containers
can now be accommodated. You can actually see the advent
of these large shipping containers and then be the largest ships
that carry tons of these shipping containers
has really affected the ports as well because you can imagine
that the old-timey ports, they are so small that these big ships
would not even fit so it's driven the expansion
of the port themselves to be able to have the capacity
to enable their ship to come in to be able to deal with the amount
of shipping containers that were talking about
being transferred between cities. I mean it's grown explosively almost. [narrator] The Arabs lead the way. They are investing billions
into the expansion of their ports. The best example can be seen in Dubai. Taking its cue from Palm Islands,
the Port of Dubai – Port of Jebel Ali – was also built in the ocean. Jebel Ali is in the Top 10
of international ports. [arabic music] Dubai is planning to surpass the ports of
Shanghai and Singapore by 2030 – and then advance
to the world’s largest port. [Mohammed Al Muallem] We have
a masterplan to 2030 that we can grow up to
70 million TEU capacity. We have the land reserved,
we have the sea reserved, and it's just a matter of
whenever we see the need is there and we see that business is growing. The demand is there,
and we're building ahead of the demand, just to make sure
that the cargo is flowing smoothly and also our partners, shipping lines,
the traders and business man are enjoying the growth
and can grow with us as well. [narrator] Terminal 2
was inaugurated in 2007. A short time later construction began
for Terminal 3, which opened in 2014. Terminal 4 opens soon, thereby bringing
container turnover capacity to 22.4 million annually. [arabic music] Shipowners have enormous power
because without trade to a harbor a city loses Revenue and so ship owners
would have the upper hand in deciding where they want to trade
and if the port didn't allow them to trade there, they were just move on
to somewhere else. So it's extremely important
that the harbors expanded to accommodate all shipowners. [narrator] Like no other city,
Shanghai exemplifies the development of port cities. An economic hub today,
Shanghai used to be a fishing village. Thanks to its outstanding location
near the Yangze Delta, Shanghai quickly grew
into a vibrant port city. Cotton, silk, porcelain and tea
were shipped around the world from here. This is where the city's
pulse could be felt – at a port right in the town center. In the 30s,
ships docked right at the Bund, Shanghai’s legendary riverfront esplanade
with its banks and magnificent hotels. The evolution of Shanghai
is typical for many large port cities. As the ports expand,
they retreat far from the city centers. These days, ships can no longer
moor along Shanghai’s waterside promenade. You have to imagine the difference
between the bustling port with people shouting and workmen,
and all of that kind of energy compared to now where things
are just moved around automatically. You actually can look around large areas
and not see that many people at all. [narrator] Today, Shanghai
has the world’s biggest port. About 40 million containers
are moved from land to ship and vice versa every year. Ships are loaded and discharged here
at altogether ten different terminals. The most significant part
of the port facility is its deep-water port Yangshan,
90 miles to the south. Up to 50 ships can berth at the same time
along its 11-km-long wharfage. Opened in 2017,
this terminal is the world’s first fully-automated facility. Driverless vehicles and robots have almost
completely taken over the work of people. At most ports today, there are only few
– if any – people who still operate the gantry cranes
that move the steel boxes. About 40 containers
need to be shifted per hour. Crane operators definitely notice
the increase in vessel size – as in Hamburg. There is definitely more work.
Especially with these ship types that we have in front of us;
you get the feeling there’s no end to the work. They hold so many containers,
and it takes forever to unload and reload them. [narrator] Gantry crane operators
work on a piece-rate basis. But will this be enough
to keep up with the heavy volume? Transshipment of the containers
is fully automated even now. I’m convinced that machines won’t be
replacing us as drivers any time soon. In many situations, we are faster
and take better action than machines. The machines we have
work in a very linear, boxy way. We drive faster and more determinedly. So I don‘t agree that our jobs as drivers
are at stake anytime soon. [narrator] However, there are already
remote-controlled gantry cranes like here in Rotterdam. Human beings can't be seen
on the Terminal grounds anywhere. The so-called "control room"
is located in the nearby office building. This is where seven people,
working in shifts, monitor all the harbor operations. The gantry crane operators
are in the next room. Especially for them,
automation was a cultural shift. Up until a few years ago,
they worked high above the containership in the crane cabin. Now they unload the containers virtually
– in front of a monitor. I miss being in the crane. I had gotten used to working up there
in stormy weather and heavy winds that rattled the cabin. It was great.
We don‘t have that here. It’s the same work but different. I like the work because it’s challenging. [narrator] The gantry crane operators
can no longer peer down through a glass floor
to see the containers. They have to rely on monitors
and the various camera perspectives. [Graham Smith] That took
the most time getting used to. Being the judge in the distance.
You have to be much more careful than I was on the other side. Not that I wasn't careful there,
but it took time to getting used to it. Now I have no problem,
but you rely on your hight meters and all the safety features
that are built into the crane. They help me do my job safely. [narrator] The highly-automated terminal
employs about 500 people. But this number is decreasing
and there’s no end in sight to the automation process. Today, the immediate colleagues of
the crane operators are machines. So-called Automated Guided Vehicles
or AGVs have revolutionized the ports. As if by magic, they drive around the port
transporting containers from the crane to the block warehouses. Armin Wieschemann helped develop
the AGV system with a team of specialists. Various sensor systems come into play
and enable the AGV to maneuver fully automatically on the harbor grounds. We installed two large transponder
antennae in the front and back. These antennae communicate
with transponders that have been installed
in the AGV driving surface. So when the antennae-bearing vehicle
moves across a transponder, the transponder transmits its info
– Which transponder am I? Where am I located exactly? –
to the antenna. The antenna in turn transmits the data
to a navigation computer that’s located in this control cabinet. [narrator] Some 20.000 transponders
have been installed grid-like into the surface. The AGV needs to know the path to take
but also how to evade other transporters. The vehicles don’t communicate
with one another but rather via a higher-level system
that specifies the route for each of the vehicles. This route should be optimally chosen
so the containers get from the gantry crane
to the warehouse crane and vice versa via the shortest route. [narrator] But the greatest achievement
is the vehicle battery. To recharge they drive autonomously
to the changing station where the battery
is replaced within minutes. These vehicles thus play a big role
in reducing harmful emissions at the port. And now specialists have even managed
to program the AGVs to get their batteries recharged when green electricity is
particularly plentiful in the power grid. With the help of AGVs,
the amount of carbon dioxide in Hamburg is to be reduced by ten-thousands of tons. The goal is to turn the port into
a transshipment point with zero emissions. Meanwhile work on the next innovation
is already underway. With the help of digitalization and AI,
autonomous ships will be navigating the harbor
and make for even smoother operations. Vincent Wegener
is heavily involved in this project. Together with the port operator,
he outfitted a patrol boat with numerous measuring devices. This is our boat test.
We call it "floating lab". The Port of Rotterdam has given us
the opportunity to make use of this vessel so we can test our software. [narrator] The eight cameras
that are installed in the boat provide a 360 degree view.
Radar and GPS transmit its position. To start with, the Floating Lab
will harvest all kinds of data. [dynamic music] The collected data will be used
to program the algorithms efficiently. A process that will be subject to
on-going optimization as the virtual captain is trained.
Various scenarios are being tested. The virtual vessel
will have to navigate in heavy swells, storms or snow
and also know how to evade other objects. There are many advantages
to having a digital captain. One of them is that a digital captain
will never get tired. Captain AI is always on hand
– either to train or to work. He never gets drunk and is more scalable. Based on an algorithm,
this technology can be used for all ships. You can’t do this with people.
We can’t convey our knowledge one-to-one. People have to be trained;
it takes 20 years to be a Senior Captain. The digital captain learns from all boots. It’s a super brain
that gets smarter every day. [narrator] Autonomous ships.
Are they the future for our ports? What role will humans still play? Will the ports be able to dispense
with them at one point? I'm not sure if ports
are going to be without completely any human interventions. I think we've seen with other Industries
that when you increase the level of autonomy it just changes
the jobs that humans do so there will always be some level
of human oversight in some capacity so that may be that they're not even sat
at the port anymore and there is some sort of remote location
and watching on cameras or whatever, but I think there will still have to be
a human element involved in some sense. There's no way
that the robots are going to be doing
absolutely everything. [narrator] So, what does
the future look like for the harbor? How far can these processes be optimized? There are still some disruptive factors
that could cancel the port’s cost concept very abruptly. A ship repair
that becomes necessary, for example. Often this would force a ship owner
to wait a long time for spare parts that need to be brought in
from another part of the world. In Rotterdam there’s a place
where start-up businesses and students deal with exactly
this problem: the RDM grounds. The former shipyard has evolved
into an innovation cluster for the port. Vincent Wegener runs his labs here too. He believes he’s found
a solution for the problem, namely by printing the necessary
spare parts with a 3D printer. [dynamic music] A robot welding arm will be programmed
with the corresponding dimensions. Layer for layer, high-grade metals
will then be applied. [dynamic music] The big advantage compared to
other technologies like forging and punching is that one can print
as many parts as one needs, when one needs them
and where one needs them. They can be printed locally
and there’s no need to wait for them to arrive from China or elsewhere. No warehouse costs accrue
because only what is needed is printed. There are so many advantages
to 3D printing. [narrator] With this technology,
Vincent Wegener and his team managed to print the world’s first
licensed ship’s propeller. A metal piece made of aluminum,
nickel and copper with a diameter of one meter
and a weight of 400 kilograms. [Vincent Wegener] We see a lot of demand
for printing metal parts on order. The Port of Rotterdam has taken on
a new purpose; it’s becoming a supplier for these parts. We envision a future
with centers like this all over the world like in Singapore, Houston or Rotterdam. Everyone will know that spare parts
can be made at these centers. [narrator] A new task for the port. He is trying to take advantage
of 3D printing as an additional service to offer. With the advent of 3D printing
almost everywhere you can see that's obviously going to go
to ports and harbors as well. So I see that's really
going to expand in the future. [narrator] The port has undergone
a transformation that has no equal. At one time, it was a place of yearning,
and the employer for an entire region. At terminals today, everything is about
efficiency, time and costs. If you take a look at how much
of the work is now automated and how quickly that has happened
you see that that is probably a sign for things to come
in other industries. [narrator] We owe
one of our greatest inventions to the ambition of a truck driver. You can sense and experience
innovations more intensively at a port than anywhere else. They are what made globalization
and turbo capitalism possible in the first place. Nowadays I can find some really
cheap gadgets from China, have it in a few weeks time and have
only spent a couple of pounds on it. And that's absolutely nuts,
and the more people are gonna be doing stuff like that
is gonna increase the demand of bigger ships for more ships traveling
as we just get more and more consumerized. [narrator] It’s about cost reduction
thru economies of scale. This also applies to passenger shipping. With unforeseen consequences
for the environment. Looking at the port
is like a glimpse into the future. A future that will change
our lives dramatically.
