>> Geller: LOOK UNDER LONDON'S BUSY STREETS, AND YOU'LL FIND MORE THAN JUST DIRT. YOU'LL FIND ANOTHER CITY. YOU WOULD HAVE NO IDEA COMING IN OFF THE STREET THAT THERE'S THIS LABYRINTH HERE. IT'S AMAZING. FROM FORGOTTEN UNDERGROUND RIVERS... SO IS THIS ONE OF THE LOST RIVERS? ...TO AN ANCIENT ROMAN COMPLEX. AND THIS IS CLEARLY ROMAN RUIN. TWO MILLENNIA OF LONDON'S TURBULENT PAST... ARE CLOSER THAN YOU THINK. >> THIS IS A BIT OF SECRET, HIDDEN LONDON, REALLY. >> Geller: COMING DOWN! LOST BUNKERS, ANCIENT CHURCHES, AND SECRET BURIAL CRYPTS ARE ALL HIDDEN UNDERGROUND. >> EVERYWHERE YOU WALK, YOU'RE WALKING ON A BURIAL. >> Geller: AND EVEN LONDON'S MOST FAMOUS LEADER, WINSTON CHURCHILL, HAD A TOP-SECRET SUBTERRANEAN LAYER. SO RIGHT OVER HERE, CHURCHILL IS SITTING WITH ALL HIS WAR MINISTERS THINKING HOW WE'RE GONNA DEFEND OUR COUNTRY AGAINST THE NAZIS -- THE FREE WORLD. WE'RE PEELING BACK THE LAYERS OF TIME TO REVEAL LONDON'S LOST CITIES. FOR 2,000 YEARS, THIS HAS BEEN ONE OF THE MOST IMPORTANT CITIES IN THE WORLD. IT'S ENDURED PLAGUES, DEVASTATING FIRES, CIVIL WAR, AND VICIOUS BOMBING RAIDS. AND THE EVIDENCE OF IT ALL IS STILL HERE -- BURIED UNDERGROUND. I'M ERIC GELLER. I'M IN LONDON, ENGLAND, EUROPE'S LARGEST CITY AND HOME TO SOME OF THE WORLD'S MOST FAMOUS LANDMARKS. EVERY YEAR, MORE THAN 27 MILLION PEOPLE FLOCK HERE TO CATCH A GLIMPSE OF HISTORY. BUT WHAT ABOUT THE HISTORY THEY CAN'T SEE? MOST LONDONERS WOULD BE ASTONISHED TO LEARN THAT DIRECT LINKS TO THEIR PAST LIE RIGHT BENEATH THEIR FEET -- HIDDEN BUNKERS BELOW SUBURBAN NEIGHBORHOODS, SECRET CRYPTS, AND TRACES OF LOST RIVERS EXIST AS LITTLE AS 15 FEET BELOW THE SURFACE. LONDON'S SECRETS ARE PLENTIFUL, AND THEY'RE ABOUT TO BE REVEALED. WHAT MOST PEOPLE DON'T KNOW IS THAT WHILE LONDON WAS GROWING UP ABOVE, THE UNDERGROUND WAS EXPANDING, AS WELL. THERE'S AN ENTIRE WORLD BURIED BENEATH THE STREETS, DATING BACK TO THE BEGINNINGS OF THIS CITY, AND WE'RE GONNA FIND IT. LONDON'S TUBE WAS THE WORLD'S FIRST UNDERGROUND RAILWAY, AND TODAY IT'S STILL GOING STRONG. EVERY DAY, 3 MILLION PEOPLE RELY ON ITS TUNNELS FOR TRANSPORT. BUT IT WASN'T THAT LONG AGO WHEN LONDONERS RELIED ON THESE SAME TUNNELS TO SAVE THEIR LIVES. >> [ SPEAKING GERMAN ] >> Geller: BY 1940, NAZI GERMANY AND ITS AXIS ARMIES HAD ROLLED THROUGH MUCH OF EUROPE. THE UNITED STATES AND RUSSIA HAD YET TO ENTER THE WAR, AND HITLER KNEW THAT BRITAIN ALONE STOOD IN THE WAY OF HIS DOMINATION OF THE CONTINENT. THE BATTLE OF BRITAIN HAD BEGUN, AND LONDON WAS THE TARGET. IN SEPTEMBER OF 1940, FIERCE BOMBING RAIDS BEGAN OVER LONDON. REFUSING TO EVACUATE, RESOLUTE LONDONERS SOUGHT PROTECTION IN THE CELLARS, UNDERPASSES, AND TUNNELS OF THE UNDERGROUND. BUT THESE MAKESHIFT BUNKERS IN LONDON'S SUBWAYS WERE NOT ENOUGH. IN ORDER TO PROTECT ITS 8 MILLION RESIDENTS, THE CITY NEEDED TO BUILD BIGGER AND STRONGER BUNKERS. THOUSANDS OF SHELTERS WERE BUILT THROUGHOUT LONDON, BUT EIGHT OF THEM WERE MORE FORTIFIED AND HIDDEN THAN THE REST. THEY WERE CALLED THE DEEP-LEVEL BUNKERS. AND THERE WAS ONE MAN WHO COULD SHOW ME DOWN. ANDREW. >> ERIC, HOW YOU DOING? >> Geller: GREAT. HIS NAME IS ANDREW SMITH. HE'S BEEN EXPLORING LONDON'S UNDERGROUND FOR OVER 20 YEARS AND KNOWS ALL OF ITS SECRETS. AND WHILE THIS INCONSPICUOUS DOOR IN THE MIDDLE OF THIS NONDESCRIPT PARKING LOT DOESN'T LOOK LIKE MUCH, IT WAS ACTUALLY THE ENTRANCE INTO A PARALLEL WORLD DATING BACK TO WORLD WAR II. >> SO THIS IS THE ORIGINAL BOMBPROOF SURFACE BUILDING. BUT TO GET DOWN TO THE SHELTER, WE'VE GOT TO GO DOWN 135 FEET. >> Geller: OH, LOOK AT THIS OLD LIFT, HUH? >> THIS IS AN ORIGINAL 1940s LIFT. AND DOWN WE GO. AND HERE WE ARE, 135 FEET UNDER LONDON. >> Geller: UNLIKE MOST BUNKERS IN LONDON, THIS ONE WASN'T LEFT ABANDONED BENEATH THE STREETS. LOT OF BOXES HERE, STORAGE BINS. WHAT'S THIS FOR? >> 300,000 DIFFERENT BOXES AND STORAGE BINS DOWN HERE, ALL STORING CORPORATE DOCUMENTATION FOR COMPANIES WHO DON'T WANT TO STORE ALL THIS STUFF IN THEIR EXPENSIVE OFFICES UP ON THE SURFACE. >> Geller: BUT THESE AREN'T JUST ORDINARY, INEXPENSIVE STORAGE SHELVES. THEY WERE ORIGINALLY BUILT AS BUNK BEDS. >> AND IN WORLD WAR II, ALL THE PEOPLE SLEPT HERE. AND WE CAN SEE THE REMAINS OF THE BUNKS. THEY'RE STILL HERE, NOW USED AS SHELVES FOR ALL THE STORAGE FACILITIES. >> Geller: YEAH, YOU SEE THE SPRINGS RIGHT HERE. THERE PROBABLY WOULD HAVE BEEN A LITTLE MATTRESS ABOVE THIS. EVEN THOUGH THERE WERE NEARLY 3,000 FEET OF TUNNELS, WITH 8,000 LONDONERS CRAMMED IN, SLEEPING ARRANGEMENTS WERE INCREDIBLY TIGHT. >> BUT YOU CAN SEE HOW NARROW THESE BUNKS ARE. AND REMEMBER, THIS IS A STACK OF THREE PEOPLE HERE -- SOMEBODY ON THE FLOOR, SOMEBODY AT THE FIRST LEVEL, AND THE THIRD PERSON ON HERE. INCREDIBLY HOT, INCREDIBLY CROWDED, PROBABLY VERY UNCOMFORTABLE, BUT EXCEEDINGLY SAFE. >> Geller: IT WAS SO SAFE THAT THIS DEEP-LEVEL BUNKER ALONE IS CREDITED WITH SAVING THOUSANDS OF LIVES DURING THE INTENSE BOMBING RAIDS OF THE 1940s. >> IT'S AN ABSOLUTELY HUGE COMPLEX HERE, AND I CAN NOW SHOW YOU JUST HOW BIG THIS IS BECAUSE HERE WE ARE IN THE MAIN SECTION. >> Geller: THIS IS HUGE. THIS IS MASSIVE. LOOK HOW GREAT THIS IS. THIS JUST SNAKES OFF IN EVERY DIRECTION. >> 135 FEET ABOVE US, WE'VE GOT CAMDEN MARKET WITH ALL THE HUSTLE AND BUSTLE THERE. THIS IS A TOTALLY DIFFERENT WORLD. >> Geller: YOU WOULD HAVE NO IDEA COMING IN OFF THE STREET THAT THERE'S THIS LABYRINTH HERE. IT'S AMAZING. IT GOES EVERY DIRECTION. >> IT'S 1,400 FOOT FROM ONE END OF THE TUNNEL TO THE OTHER. AND REMEMBER, THERE'S TWO OF THESE TUNNELS, AS WELL. THERE'S OVER A MILE OF TUNNEL DOWN HERE. >> Geller: AS AIR RAID SIRENS SOUNDED OVERHEAD, PANICKED LONDONERS POURED INTO THE DEEP-LEVEL SHELTER. BUT WITH SO MANY PEOPLE RUSHING IN AT A MOMENT'S NOTICE, HOW IS IT THAT NO ONE GOT TRAMPLED? ENGINEERS CAME UP WITH AN INGENIOUS PLAN. >> THIS IS THE SPIRAL STAIRCASE THAT LEADS UP FROM THIS FLOOR. BUT IN ORDER TO GET TO THE OTHER LEVEL IN THIS BUNKER, THERE WAS ANOTHER STAIRCASE THAT WAS PUT IN THAT RUNS THE OPPOSITE WAY AROUND THE LIFT SHAFT. AND HERE IT IS. SO YOU HAVE ONE STAIRCASE GOING ONE WAY AND ONE STAIRCASE GOING THE OTHER. >> Geller: THE STAIRCASE WAS DESIGNED IN THE SHAPE OF THE DOUBLE HELIX TO ENSURE THAT EVERY LEVEL OF THE SHELTER HAD ONE WAY IN AND ONE WAY OUT. 10 DEEP-LEVEL SHELTERS JUST LIKE THIS ONE WERE PLANNED, BUT ONLY EIGHT WERE BUILT, AND THEY ARE EIGHT OF THE MOST AMAZING ENGINEERING MARVELS OF THE TIME. MOST BUNKERS WERE 10 TO 50 FEET BELOW THE GROUND, BUT THE DEEP-LEVEL SHELTERS WERE AT LEAST 100 FEET BELOW THE STREETS, MAKING THEM PRACTICALLY BOMBPROOF. IN FACT, ANDREW SAYS, THE ONLY WAY THE DEEP-LEVEL SHELTERS COULD BE DESTROYED IS IF A BOMB WERE DROPPED DOWN THE MAIN LIFT SHAFT THAT ANDREW AND I HAD TAKEN DOWN HERE. BUT THAT WOULD HAVE BEEN UTTERLY IMPOSSIBLE. A GERMAN BOMBER TRAVELING AT 200 MILES PER HOUR AT 10,000 FEET WOULD HAVE HAD TO DROP THE BOMBS PERFECTLY VERTICAL TO MAKE IT INSIDE THE SHAFT -- A SHAFT CAMOUFLAGED BY ANOTHER BOMBPROOF SURFACE BUILDING. THE BOMB THEN WOULD HAVE HAD TO TRAVEL 135 FEET THROUGH THE SHAFT, AND, AFTER ALL THAT, IT WOULD HAVE HAD TO DETONATE INSIDE THE SHELTER. IT'S AN IMPOSSIBLE SCENARIO, MEANING THIS SHELTER WAS TRULY BOMBPROOF. TELL ME, HOW DID THEY BUILD THIS PLACE? >> TUNNELING DOWN HERE WAS CARRIED OUT 24 HOURS A DAY, 7 DAYS A WEEK ON AN ALTERNATING-SHIFT SYSTEM. BUT THE ACTUAL MUD WAS ONLY REMOVED FROM THE SURFACE UNDER THE COVER OF NIGHT. >> Geller: DARKNESS KEPT THE LOCATION TOP SECRET, AND THE DESIGN WAS UNIQUE. TWO PARALLEL TUNNELS WERE DUG, EACH 16 FEET IN DIAMETER AND NEARLY 400 FEET LONG. AND ALL OF IT WAS BURIED 100 TO 135 FEET BENEATH THE GROUND. SO THE DEEP-LEVEL BUNKERS WERE SAFE FROM BOMBS, BUT WHAT ABOUT THE ELEMENTS? AT 135 FEET BELOW STREET LEVEL, THE SOIL ALONE WAS PUTTING ALMOST 300 MILLION POUNDS OF WEIGHT ON THE STRUCTURE. THEY REINFORCED EACH SECTION WITH MASSIVE RINGS MADE OF STEEL AND CONCRETE. BETWEEN EACH RING, A THICK LAYER OF HEMP WAS USED TO WATERPROOF THE JOINTS. THE RINGS WERE THEN HELD TOGETHER BY 2-INCH-THICK STEEL BOLTS. >> SO HERE WE CAN SEE QUITE CLEARLY THE ACTUAL ENGINEERING THAT WAS PUT TOGETHER -- ALL THESE DIFFERENT STEEL SECTIONS BOLTED TOGETHER WITH THESE MASSIVE 2-INCH BOLTS. THIS PARTICULAR FORM OF CONSTRUCTION WAS DESIGNED TO WITHSTAND 6,000 POUNDS OF PRESSURE PER SQUARE INCH. >> Geller: I HEAR SOME PRESSURE RIGHT NOW. >> YES, THAT'S ALL YOU CAN HEAR. THAT'S ACTUALLY THE NORTHERN LINE SUBWAY TRAIN. >> Geller: AND HOW FAR ABOVE THAT IS THE NORTHERN LINE? >> IT'S JUST 15 FEET ABOVE US. WE'RE THAT DEEP HERE. >> Geller: AND THIS HAS NEVER BEEN COMPROMISED BEFORE, EVEN FROM THE WEIGHT OF THE TRAIN? >> NOPE, THE 600 TONS OF TRAIN GOES RATTLING THROUGH IT 35 MILES AN HOUR, AND THIS DOESN'T EVEN SHUDDER. >> Geller: BUT WHAT DO YOU DO WITH SUCH A WELL-DESIGNED BUNKER AFTER THE WAR? BRITISH ENGINEERS HAD BEEN PLANNING TO TRANSFORM THE NOW-VACANT SHELTERS INTO LONDON'S NEWEST EXPRESS SUBWAY LINES. >> LET'S SEE, WE'RE NOW STANDING ON WHAT WOULD HAVE BEEN THE ACTUAL TRACK BED. OKAY, SO HAD THIS BEEN CONVERTED AT THE END OF WORLD WAR II, THE RAILS AND THE SLEEPERS WOULD HAVE BEEN SUNK INTO THIS CONCRETE THAT WE'RE NOW STANDING ON, AND THE TRAIN WOULD HAVE BEEN HURTLING THROUGH HERE AT PROBABLY 40, 50 MILES AN HOUR. AND THE PEOPLE WOULD HAVE BEEN ABLE TO GET ON AND OFF THE TRAINS HERE AND ON THE PROPOSED HIGH-SPEED TRAIN LINE. >> Geller: DUE TO LACK OF MONEY, THE PLANS TO BUILD THE EXPRESS ROUTES WERE SCRAPPED. BUT THIS TIME CAPSULE OF LONDON'S PAST IS STILL HERE, AND IT'S CLOSER THAN YOU THINK. THE ROMANS LIVED HERE FOR OVER 400 YEARS, AND THEIR GREAT EMPIRE LEFT MANY CLUES BEHIND. BUT DIGGING THEM UP IN THIS BUSY METROPOLIS ISN'T EASY. I ENLISTED THE HELP OF JENNY HALL, A LEADING EXPERT ON ROMAN LONDON. JENNY? >> YES, HELLO. >> Geller: HI, JENNY, THANK YOU FOR MEETING WITH ME. THE CITY OF LONDON CORPORATION HELPS TO FUND AND MAINTAIN THIS SUBTERRANEAN SITE AND GAVE JENNY PERMISSION TO SHOW IT TO ME. FEW PEOPLE KNOW IT EXISTS. JENNY, IT DOESN'T EXACTLY LOOK LIKE THERE'S ROMAN RUINS AROUND HERE. >> NOT THAT YOU CAN SEE HERE. BUT WOULD YOU BELIEVE THIS ROAD USED TO BE WHERE THE ROMAN WATERFRONT WAS? THE ROMANS ACTUALLY HAD THIS AREA AS THEIR WATERFRONT, THEIR WAREHOUSES, THEIR KEYS. BOATS WOULD HAVE BEEN MOORED UP HERE AND UNLOADING GOODS. DOESN'T REALLY LOOK LIKE THAT NOW, DOES IT? >> Geller: NO, IT DOESN'T. IN THE 2nd CENTURY, THIS WOULD HAVE BEEN THE RIVER THAMES? >> IT WOULD HAVE BEEN, YES. >> Geller: ALMOST 2,000 YEARS AGO, THIS BUSY STREET WAS A BUSTLING RIVERSIDE WHARF. IN FACT, THE RIVER HAS MOVED OVER 100 YARDS AWAY FROM THE 2nd-CENTURY SHORELINE. IT ALL STARTED IN 43 A.D., WHEN THE ROMANS USED THE LAND ALONG THE THAMES AS A MILITARY STORAGE DEPOT DURING THEIR INVASION OF BRITAIN. WITHIN A FEW YEARS, THE ROMAN CITY OF LONDINIUM WAS BORN. BY THE BEGINNING OF THE 2nd CENTURY, LONDINIUM WAS THE CAPITAL OF THE ROMAN PROVINCE OF BRITANNIA. ITS STRATEGIC LOCATION ALONG THE RIVER MADE IT IDEAL FOR TRADE, AND LIKE THE MODERN CITY, IT ATTRACTED PEOPLE FROM ALL OVER THE WORLD, ESPECIALLY TO ITS WATERFRONT. AS THE CITY GREW, THE ROMANS BUILT MANY WHARFS ALONG THE RIVERFRONT -- PRETTY AMAZING WHEN YOU REALIZE THEY HAD NO MODERN MACHINERY. USING HUGE TIMBERS, THEY MADE THE BASE OF THE WHARF SEVERAL YARDS INTO THE RIVER. BEHIND THE TIMBER WALLS, THEY ACTUALLY CREATED LAND BY FILLING IN THE EMPTY SPACE THAT WAS ONCE THE RIVER WITH TONS OF DEBRIS LEFT OVER FROM CONSTRUCTION. BUT CREATING NEW LAND CAUSED OTHER PROBLEMS. THE MIGHTY RIVER THAMES BEGAN TO SHRINK. THE MAN-MADE WHARFS ALSO ACTED AS DAMS, WHICH BEGAN TO COLLECT SILT AND DEBRIS FROM UPSTREAM. OVER TIME, THE SILT FILLED IN THE SHORELINE, AND THE RIVER BECAME SMALLER AND SMALLER TO THE SIZE WE SEE TODAY. TODAY, MOST PEOPLE FORGET THAT THIS ROAD WAS ONCE A RIVER OR THAT WATERFRONT ROMAN RUINS COULD BE BURIED ANYWHERE ALONGSIDE THIS STREET. SO, CAN I HAVE A LOOK AT THESE RUINS? >> YES, COME WITH ME. >> Geller: JUST 20 FEET BELOW A MODERN OFFICE BUILDING, WE WERE STANDING IN THE MIDDLE OF ANCIENT ROME. AND THIS IS CLEARLY ROMAN RUINS. >> THESE REMAINS ARE SORT OF CLOSE TO WHAT WAS THE ROMAN WATERFRONT. AND ALTHOUGH WE'RE BELOWGROUND HERE, THE ROMAN WATERFRONT WAS ONLY A MATTER OF SOME FEET AWAY FROM US. >> Geller: BUT THIS WASN'T JUST AN OLD ROAD OR WALL -- THIS WAS A SOPHISTICATED ROMAN BATHHOUSE COMPLEX. YOU'VE GOT AN ENTIRE ROMAN BATH DOWN HERE? >> YES, THE BATH IS IN THE DISTANCE, AND THIS IS THE HOUSE THAT WAS ATTACHED TO IT. IT COULD HAVE BEEN THAT IT WAS SOME SORT OF HOTEL OR INN, PEOPLE ARRIVING BY BOAT, GETTING OFF THE BOAT, NEEDING SOMEWHERE TO STAY OVERNIGHT WHERE THEY COULD GET CLEAN BEFORE TRAVELING ON TO THE REST OF THE PROVINCE. >> Geller: BY THE 2nd CENTURY, THE ROMAN EMPIRE WAS MASSIVE, SPANNING THREE CONTINENTS, FROM THE MIDDLE EAST ACROSS NORTH AFRICA AND COVERING VIRTUALLY ALL OF PRESENT-DAY EUROPE. BY THE 5th CENTURY, ROMAN INFLUENCE IN BRITAIN BEGAN TO FADE, AND LONDINIUM BECAME BURIED BENEATH A MOUNTAIN OF URBAN SPRAWL. WHEN THE INDUSTRIAL REVOLUTION HIT IN THE MID-1800s, THE ROMAN CITY DISAPPEARED ENTIRELY... EXCEPT FOR A FEW SITES LIKE THIS ONE THAT WERE ACTUALLY SAVED BY THE BUILDINGS THAT BURIED THEM. HOW FAR DOWN BELOW STREET LEVEL ARE WE? >> WE'RE ABOUT 20 FEET BELOW PRESENT-DAY STREET LEVEL 'CAUSE YOU HAVE TO IMAGINE, THAT OVER THE CENTURIES -- AND THE ROMANS BUILT THE TOWN NEARLY 2,000 YEARS AGO -- THERE'S BEEN A SOLID BUILDUP OF RUBBISH. SO THAT AS ARCHAEOLOGISTS, WHEN WE DIG DOWN, WE GET THIS SANDWICH-HISTORICAL LAYER WITH THE ROMANS AT THE BOTTOM. >> Geller: WE WERE AT THE BOTTOM OF THIS ARCHAEOLOGICAL SANDWICH. BUT HOW WAS THIS ROMAN BUILDING SAVED WHEN SO MANY WERE DESTROYED? IN THE 19th CENTURY, THIS BUILDING WAS ORIGINALLY THE COAL EXCHANGE. BUILDERS CREATED A CAVITY SURROUNDING AND PROTECTING THE ORIGINAL ROMAN SITE FROM THE TONS OF PRESSURE COMING DOWN FROM THE COAL EXCHANGE UP ABOVE. LATER, ENGINEERS OF THE CONTEMPORARY BUILDING FOLLOWED SUIT, PLACING CONCRETE-REINFORCED SUPPORT BEAMS AROUND THE BATHHOUSE TO SUPPORT THE CAVITY AND PRESERVE THIS PIECE OF ANCIENT ROME. BUT THERE'S MORE. INCREDIBLY, THESE REMAINS, PROTECTED BY THE MODERN BUILDING UP ABOVE, CONTAINED A SOPHISTICATED CENTRAL HEATING SYSTEM, A TESTAMENT TO THE POWER OF ROMAN ENGINEERING. THAT LOOKS LIKE A FURNACE. THAT'S WHAT IT LOOKS LIKE TO ME. >> YEAH, THAT IS THE FURNACE. >> Geller: SO HOW WAS THIS FURNACE OPERATED? >> YOU HAD TO HAVE YOUR FIRE BURNING INSIDE THAT LITTLE TILED ARCHWAY. SO SOME POOR SLAVE WOULD HAVE BEEN IN THE OPEN YARD HERE PUTTING WOOD INTO THAT ARCHWAY, KEEPING THAT FIRE GOING. SO THAT WE'VE GOT THE COLUMNS OF TILES THAT WOULD HAVE SUPPORTED THE FLOOR, THE HOT AIR WOULD HAVE FLOWED UNDERNEATH THOSE INTO THE VARIOUS ROOMS. >> Geller: IT'S RIDICULOUSLY SOPHISTICATED, ISN'T IT? >> IT IS. >> Geller: THE ROMAN DESIGNS WERE NOT ONLY HIGHLY SOPHISTICATED, BUT THEY WERE ALSO CENTURIES AHEAD OF THEIR TIME. AND BELIEVE IT OR NOT, SOME, IF NOT MOST, ARE STILL IN USE TODAY. >> CAN YOU SEE -- THERE'S A CLAY BOX BUILT INTO THE WALL. >> Geller: THE GROOVES IN IT ACTUALLY LOOK VERY SIMILAR TO THE CEMENT CINDERS. >> YES, IT MEANT THAT YOU COULD ACTUALLY USE THE SIDE OF THAT BOX TO ACTUALLY PLASTER AGAINST. >> Geller: THAT'S<i> EXACTLY</i> THE SAME THING AS WHAT WE HAVE IN THE CONTEMPORARY BUILDING. THESE PLASTER BLOCKS ARE THE SAME AS TODAY'S CINDER BLOCKS -- A VERY COMMON MATERIAL USED IN MODERN BUILDING. IN FACT, ROME'S INFLUENCE CAN BE SEEN ALL AROUND THE MODERN CITY. BUT FEW KNOW SITES LIKE THIS STILL EXIST. DO PEOPLE HAVE ANY IDEA THAT THIS EXISTS DOWN HERE? >> NO, THIS IS RATHER A SECRET. THIS IS HIDDEN AWAY. IT'S IMPORTANT THAT WE PRESERVE THESE REMAINS BECAUSE THESE BIG OFFICE BLOCKS TAKE OUT ALL THE ARCHAEOLOGY. SO IT'S VERY IMPORTANT TO US THAT WE PRESERVE WHAT'S LEFT. >> Geller: MOST OF ROMAN LONDON HAS ALREADY DISAPPEARED BENEATH TODAY'S CITY, BUT THE LEGACY OF THE INGENIOUS ROMAN ENGINEERING IS STILL ALIVE TODAY. A RIVER CAN'T JUST BE TURNED OFF LIKE A TAP, BUT THAT'S JUST WHAT CITY ENGINEERS DID. WHEN THE ROMANS FOUNDED THE CITY IN THE 1st CENTURY, THERE WERE NEARLY A DOZEN RIVERS THAT FLOWED THROUGH OPEN FIELDS INTO THE THAMES. TODAY, THEY'VE ALL BUT VANISHED. BUT THEY'RE NOT ENTIRELY GONE. IF YOU KNOW WHERE TO LOOK, YOU CAN STILL SEE SIGNS OF THESE LONG-LOST RIVERS. IN FACT, THE CITY'S FAMOUS STREETS AND PARKS STILL BEAR THEIR NAMES. FLEET STREET RUNS ATOP THE OLD FLEET RIVER. AND YEARS AGO, THE CARS DRIVING DOWN FARRINGTON STREET WOULD HAVE BEEN BOATS. BUT LONDON'S RIVERS DIDN'T DRY UP. MANY ARE STILL FLOWING, JUST NOT WITH WATER. THE RIVERS OF LONDON WERE COVERED UP ON PURPOSE. BUT WHY WOULD A CITY ACTUALLY BUILD ON TOP OF THE RIVERS THEY DEPEND ON FOR TRADE AND DRINKING WATER? AT ITS HEIGHT, MILLIONS OF PEOPLE FLOCKED TO LONDON, AND THAT MEANT TWO THINGS -- NUMBER ONE, THEY NEEDED BUILDING SPACE, AND NUMBER TWO, THEY NEEDED A MASSIVE SEWER SYSTEM TO HANDLE ALL OF THE SEWAGE. THAT'S RIGHT -- THE RIVERS BECAME SEWERS. PAVING OVER THE RIVERS GAVE LONDONERS THE SPACE AND REDIRECTING THE RIVERS' FLOW HELPED FLUSH OUT THE WASTE OF THE GROWING CITY. IT'S BEEN OVER 130 YEARS SINCE THE RIVERS WERE COMPLETELY COVERED. AND TODAY, ALMOST NO ONE KNOWS HOW TO LOCATE THEM EXCEPT FOR A MAN WHO SPENT HIS LIFE UNDERGROUND. ALL RIGHT, I THINK THIS IS THE PLACE. [ KNOCK ON DOOR ] BEN NITHSDALE IS A FORMER FLUSHER, OR WASTEWATER OPERATOR. BEN, BY CHANCE? >> HELLO, YOU MUST BE ERIC. >> Geller: BEN WORKED FOR THAMES WATER, THE CITY'S WATER UTILITY, FOR 30 YEARS... >> THERE'S A KIT FOR YOU THERE, WHICH I HOPE IS YOUR SIZE. >> Geller: ...AND KNOWS THE SEWERS LIKE HIS OWN BACKYARD. HE'S AGREED TO TAKE ME BENEATH THE PAVEMENT, TO LONDON'S LOST RIVERS-TURNED-SEWERS. >> WHERE WE'RE GOING, THE FLOOR IS LIKE GLASS, SO YOU HAVE TO BE QUITE CAREFUL. >> Geller: IT'S A SUBTERRANEAN WORLD RESPONSIBLE FOR TAKING AWAY THE WASTE OF 13 MILLION PEOPLE. >> WHERE WE'RE GOING TONIGHT IS A STORM SEWER. WHEN IT RAINS, IT FILLS UP QUITE QUICKLY. >> Geller: SO, YOU'RE NOT EXPECTING A FLASH FLOOD, BUT IF YOU GOT ONE, WHAT WOULD HAPPEN DOWN THERE? >> WE'D HAVE TO GET OUT IMMEDIATELY BECAUSE THE WATER COULD RISE UP QUITE QUICKLY, AND WE COULD BE WASHED AWAY. SO IT IS POTENTIALLY QUITE DANGEROUS. >> Geller: LET'S HOPE THERE'S NO RAIN TONIGHT. FLOODING WASN'T THE ONLY DANGER IN THE SEWERS. NOW, THIS LOOKS LIKE A STEP-THROUGH RIGHT HERE? I GOT THIS RIGHT? >> PUT YOUR OTHER FOOT IN HERE. >> Geller: BEN GAVE ME A PROTECTIVE SUIT TO GUARD AGAINST INFECTION AND A BEEPING MONITOR TO TRACK TOXIC GAS LEVELS. ONCE WE GOT DOWN, THERE WOULD BE A MIX OF DEADLY HYDROGEN SULFIDE AND NONTOXIC BUT HIGHLY FLAMMABLE METHANE GAS. THIS IS STYLISH. WE COULD FORM A BOY BAND ALMOST, COULDN'T WE? >> WELL, YOU NEVER GET MUGGED WHEN YOU'RE DRESSED LIKE THIS. >> Geller: WELL, YOU DO WHERE I COME FROM. >> [ LAUGHS ] >> Geller: BEN SHOWED ME A MAP OF THE CITY'S SUBTERRANEAN SEWERS. THERE ARE NEARLY A DOZEN RIVERS THAT HAVE BEEN "SEWERIZED" -- ESSENTIALLY PAVED OVER AND REROUTED INTO MAN-MADE TUNNELS. AND THESE ARE ALL SUBTERRANEAN, HIDDEN RIVERS? >> ALMOST ENTIRELY. ON THE SOUTH SIDE OF LONDON, SEVERAL OF THEM ARE STILL OPEN FOR STRETCHES. BUT ALL OF THE NORTH-SIDE ONES ARE COMPLETELY ENCLOSED, LIKE THE ONE YOU'RE SEEING TONIGHT. ALL RIGHT, ERIC, THIS WAY. >> Geller: ALL RIGHT. >> WE'RE GONNA GO ON THIS WAGON HERE. >> Geller: OKAY. THE ENTRANCES TO THE SEWERS ARE KEPT SECRET FROM THE PUBLIC, SO WE CAN'T SHOW THE EXACT LOCATION. >> OKAY, YOU'RE READY. >> Geller: BUT I CAN TELL YOU IT'S RIGHT BENEATH ONE OF LONDON'S MOST FAMOUS UPSCALE STORES. COMING DOWN! ALL RIGHT. NOTHING TO IT. >> NOW, WHEN YOU STEP OFF, TRY AND STEP OUT INTO THE MIDDLE. >> Geller: ALL RIGHT. LITTLE SLICK. >> YEP. GOOD. >> Geller: THIS IS COOL. ALTHOUGH IT'S A TRICKLE NOW, ALMOST 50,000 GALLONS OF SEWAGE FLOW THROUGH THE SEWERS EACH DAY. THE SMELL WAS UNBELIEVABLE. BUT THIS WASN'T A SURPRISE WHEN YOU THINK OF THE MILLIONS OF TOILETS FLUSHING TONS OF WASTE DOWN HERE EVERY DAY. BUT WHAT WAS SURPRISING WAS THAT THESE TUNNELS WERE ONCE SOME OF LONDON'S BUSIEST WATERWAYS. IS THIS ACTUAL RIVER WATER THAT WE'RE GETTING? >> YES, IT'S A MIXTURE OF GROUNDWATER AND SEWAGE. >> Geller: SO IS THIS ONE OF THE LOST RIVERS? >> YES, THIS IS ONE OF THE STREAMS THAT USED TO BE OPEN THROUGH WEST LONDON, AND IT WAS COVERED OVER DURING THE 19th CENTURY. >> Geller: 200 YEARS AGO, WE WOULD HAVE BEEN STANDING AT THE BOTTOM OF THE WESTBOURNE RIVER. DIRECTLY ABOVE US WOULD HAVE BEEN LONDON'S INFAMOUS WATERFRONT. AS THE CITY GREW IN THE 17th AND 18th CENTURIES, SO DID ITS SLUMS FULL OF DENS OF SEX AND DRUGS. RANELAGH GARDENS, IN PARTICULAR, WAS KNOWN AS A PLACE OF PUBLIC AMUSEMENT NOTORIOUS FOR DRUG DEALERS AND PROSTITUTES. >> AND IN THE 17th CENTURY, RANELAGH GARDENS IS WHERE YOU WENT FOR SEX AND DRUGS AND PROSTITUTES. BUT IT'S GONE NOW, UNFORTUNATELY. >> Geller: WHILE THE ILLEGAL ACTIVITIES ARE GONE, THE GARDEN STILL EXISTS APPROXIMATELY 10 FEET ABOVE. AND THE RIVER THAT USED TO RUN BELOW IT IS NOW THE SEWER WE WERE STANDING IN. BUT EXACTLY HOW WERE THE RIVERS SEWERIZED? IT HAPPENED IN A SERIES OF PHASES. THE FIRST PHASE CAME IN THE 1700s. BY THEN, MUCH OF LONDON'S RIVERS WERE COVERED TO HIDE POLLUTION AND TO FREE UP SPACE FOR THE CROWDED CITY. SECTION BY SECTION, THE RIVERS BEGAN TO DISAPPEAR BENEATH THE STREETS. THE ONCE FREE-FLOWING RIVERS WERE TRANSFORMED INTO SEWERS CARRYING WASTE INTO THE THAMES, WHERE IT TRAVELED THROUGH THE HEART OF THE CITY AND EVENTUALLY OUT TO SEA. BUT THAT MEANT THE THAMES WAS AN OPEN SEWER. AND WITH THE ADVENT OF FLUSHING TOILETS, THE WHOLE CITY WAS PRACTICALLY OVERFLOWING WITH WASTE, CREATING WHAT WAS CALLED THE GREAT STINK OF 1858. BUT THE SMELL WAS THE LEAST OF THE PROBLEMS. SIX OF THE NINE WATER SUPPLIERS OF THE CITY DREW UNFILTERED WATER FROM THE THAMES. ENDLESS OUTBREAKS OF CHOLERA CRIPPLED LONDON. SOMETHING HAD TO BE DONE. A PLAN WAS PUT INTO PLACE TO DIVERT THE SEWAGE FLOWING THROUGH THE UNDERGROUND RIVERS AWAY FROM THE CITY BY DUMPING THE WASTE AT A LOWER POINT ALONG THE THAMES. SO IN 1859, THE CITY LAUNCHED A NEW PHASE OF THE SEWAGE-OVERHAUL PLAN. IT WAS A HUGE AND AMBITIOUS CIVIL-ENGINEERING PROJECT. ENGINEERS DUG NEW TUNNELS AND DEEPENED THOSE THAT ALREADY EXISTED. 1,300 MILES OF TUNNELS WERE BUILT ALONGSIDE THE RIVERS, AND 13,000 MILES OF PIPES AND DRAINS WERE PUT IN. 318 MILLION BRICKS WERE LAID, AND OVER 3.5 MILLION CUBIC YARDS OF EARTH WERE EXCAVATED. BUT MOST IMPORTANTLY, THEY BUILT 100-MILE-LONG SEWERS THAT RAN ALONG EACH SIDE OF THE RIVER THAMES. USING THE CUT-AND-COVER METHOD, THEY DUG A SECTION OF EARTH USING PICKAXES AND SHOVELS, COVERED AND SECURED THE TUNNEL WITH A CIRCLE OF BRICKS, THEN MOVED ON TO THE NEXT SECTION. WHEN THESE RIVERSIDE TUNNELS WERE COMPLETED, THEY INTERCEPTED THE OLD SEWERS' STEADY FLOW OF WASTE AND DROPPED IT OFF FURTHER DOWNSTREAM. THESE TUNNELS ARE STILL IN USE TODAY. THIS MASSIVE SEWER PROJECT TOOK 16 YEARS AND 22,000 WORKERS TO COMPLETE. FINALLY, LONDON'S WASTE PROBLEM WAS IN CHECK. BUT WITH THOUSANDS OF MILES OF EMPTY SPACE, HOW DOES THE CITY ABOVE NOT CAVE IN TO THE TUNNELS BELOW? NOW, THERE ARE MASSIVE DOUBLE-DECKER BUSES THAT ARE ALWAYS GOING DOWN THIS STREET. HOW COME THIS THING DOESN'T CAVE IN? >> WELL, AS YOU CAN SEE, IT'S A CIRCULAR-ARCH CONSTRUCTION, AS THOUGHT UP BY THE ROMANS, AND IT'S VERY STRONG, AND IT'S WELL ABLE TO WITHSTAND THE WEIGHT OF HEAVY TRAFFIC. >> Geller: TODAY, APPROXIMATELY 40 FLUSHERS LIKE BEN MAINTAIN THIS SAME SYSTEM. IT'S A DANGEROUS AND FOUL PLACE TO SPEND AN EVENING. MOST LONDONERS MAY NEVER KNOW ABOUT THE LOST RIVERS BENEATH THEIR NEIGHBORHOOD, BUT BELIEVE ME, THEY'RE LUCKY THIS MASSIVE ENGINEERING MIRACLE IS BELOWGROUND. WESTMINSTER ABBEY IS THE CORONATION CHURCH OF ENGLAND, AND ALL THE KINGS AND QUEENS OF GREAT BRITAIN SINCE THE 13th CENTURY HAVE BEEN CROWNED THERE. WESTMINSTER IS STILL A PRACTICING CHURCH WITH DAILY MASSES. THOUSANDS OF PEOPLE PASS THROUGH ITS DOORS EACH DAY. BUT I WAS ABOUT TO SEE SOMETHING THEY WOULD NEVER SEE. THERE'S A RUMOR THAT SOMETHING EXISTS BENEATH WESTMINSTER ABBEY. I MET WITH CURATOR VANESSA SIMEONI. >> THAT'S RIGHT. WE HAVE A COUPLE OF INSPECTION HATCHES WHERE WE CAN ACTUALLY GO DOWN AND SEE THOUSANDS OF BURIALS. SO EVERYWHERE YOU WALK, YOU'RE WALKING ON A BURIAL. >> Geller: SO NOT ONLY WAS I WALKING THROUGH ONE OF LONDON'S MOST RECOGNIZABLE LANDMARKS, I WAS ALSO JUST A FEW FEET ABOVE A SECRET BURIAL GROUND. THROUGHOUT THE ABBEY ARE FOUR INSPECTION PITS... HEY, HEY, HEY, THERE IS SOMETHING DOWN THERE. ...WHICH ALLOW MAINTENANCE CREWS TO OCCASIONALLY PERFORM CONSERVATION EFFORTS. AND THEY ALSO PROVIDE ACCESS TO THE TOMBS. >> THIS IS ANOTHER INSPECTION PIT. IT'S A BIT BIGGER. >> Geller: THE ABBEY ABOVE WAS 800 YEARS OLD, BUT THE 4-FOOT CAVITY FULL OF TOMBS BENEATH THE FLOOR WAS EVEN OLDER, DATING BACK TO THE 11th CENTURY. INCREDIBLY, ALONGSIDE THE TOMBS WERE THE FOUNDATIONS OF A SECOND ANCIENT CHURCH 200 YEARS OLDER THAN THE ABBEY ABOVE. >> WHAT YOU'RE ACTUALLY SEEING DOWN THERE, ERIC, IS THE 11th-CENTURY APSE, WHICH WAS THE CURVED END OF THE CHAPEL. >> Geller: LOOKS LIKE SOMEBODY PUT A FEW METAL SUPPORTS THERE, SOME CROSS SPIRES TO MAKE SURE THAT THIS WASN'T GONNA CRUMBLE DOWN. YOU CAN SEE WHERE THE DIFFERENCE IS, WHERE THIS BRICK ENDS AT ABOUT FROM HERE DOWN TO MY ARM -- A GOOD 3 FEET OR SO -- AND THIS WOULD BE THE ORIGINAL MASONRY OF THE ORIGINAL FOUNDATION. >> YEP, THAT'S EXACTLY IT. >> Geller: BUT HOW DID AN ANCIENT CHURCH GET BURIED BENEATH A MODERN ONE? IN 1065, KING EDWARD, WHOSE REMAINS ARE STILL BURIED BENEATH THE MAIN ALTAR, FUNDED THE BUILDING OF A NEW MINSTER, AN OLD ENGLISH WORD MEANING THE CHURCH OF A MONASTERY. HE BUILT HIS MINSTER RIGHT ON TOP OF THE OLD ONE. THE NEW CHURCH BECAME KNOWN AS THE WEST MINSTER, AND THE ANCIENT CHURCH BENEATH IT BECAME THE FOUNDATION THAT HELPS HOLD UP WESTMINSTER ABBEY TODAY. WESTMINSTER ABBEY IS MADE UP OF NEARLY 1.4 MILLION CUBIC FEET OF LIMESTONE. SO WITH A BALLPARK WEIGHT OF 200 MILLION POUNDS PRESSING DOWN ON ITS WALLS, IT'S AMAZING HOW WELL ALL OF THIS IS PRESERVED. THAT WAS QUITE A TRIP. >> IT'S GOOD FUN. >> Geller: TODAY, THE ABBEY IS AN ENGINEERING MARVEL, AND WHO WOULD HAVE GUESSED IT'S RIGHT ON TOP OF ANOTHER CHURCH AND A BURIAL GROUND FULL OF LONDON'S MOST FAMOUS RESIDENTS? BUT THERE'S MORE THAN JUST ROYALTY BURIED IN LONDON'S UNDERWORLD, AND WESTMINSTER ABBEY ISN'T THE ONLY CHURCH WHERE I'D COME SO CLOSE TO THE DEAD. LONDON'S HISTORY GOES BACK MORE THAN 2,000 YEARS, AND NOWHERE IS THAT MORE PROMINENT THAN ST. BRIDE'S CHURCH. ONE OF LONDON'S EARLIEST ROMAN SITES, A BOMB LEVELED THE PLACE TO THE GROUND DURING WORLD WAR II. THE FOLLOWING EXCAVATIONS DISCOVERED MORE THAN JUST DIRT AND RUBBLE -- THEY DISCOVERED A LOST WORLD. ST. BRIDE'S CHURCH DATES BACK TO THE FIRST MOMENT THE ROMANS SET FOOT IN LONDON. THIS SMALL CHURCH'S WALLS HIDE A GRISLY SECRET THAT NOT MANY PEOPLE KNOW EXIST. AND FOR HUNDREDS OF YEARS, IT'S BEEN RIGHT BELOW THEIR FEET. CHURCH RECTOR DAVID MEARA WAS ABOUT TO GIVE ME FULL ACCESS TO THE OFF-LIMIT CHAMBERS OF THIS ANCIENT CRYPT. DAVID. >> ERIC. HI. WELCOME TO ST. BRIDE. A CHURCH HAS STOOD ON THIS SITE FOR ABOUT 1,500 YEARS. THE ORIGINAL CHURCH WAS FOUNDED BY ST. BRIDGIT, SOME BRIDES, IN THE 5th CENTURY. >> Geller: STARTING WITH THE ROMANS IN THE 2nd CENTURY, THIS SMALL CHURCH HAS BEEN DESTROYED AND REBUILT ROUGHLY EVERY 200 YEARS. IN 1703, FAMED ARCHITECT CHRISTOPHER WREN DESIGNED THE SEVENTH VERSION OF THE CHURCH. THEN IN 1940, ANOTHER GREAT CATASTROPHE STRUCK -- THE NAZIS BOMBED LONDON. >> THE 29th OF DECEMBER, 1940, DURING ONE OF THE GREAT FIRE RAIDS, THE CHURCH TOOK A DIRECT HIT FROM A FIRE BOMB. THE OUTER WALLS AND THE TOWER AND SPIRE SURVIVED. BUT THE REST OF IT WAS A COMPLETE, BURNT-OUT SHELL. >> Geller: ST. BRIDE'S WAS COMPLETELY OBLITERATED, AND PLANS WERE MADE TO REBUILD THE CHURCH FOR THE EIGHTH TIME. BUT THIS TIME, IT WAS A DIFFERENT STORY. WHEN THEY BEGAN TO CLEAR AWAY THE DEBRIS, THEY ACTUALLY FOUND AN ANCIENT ROMAN ROAD AND A MYSTERIOUS MASS GRAVE CALLED A CHARNEL HOUSE. SO UP UNTIL WORLD WAR II, THEY HAD NO IDEA THAT THERE WAS A THOUSAND YEARS OF HISTORY ON THIS VERY SITE. >> IT WAS A VERY EXCITING MOMENT. THEY DISCOVERED THE ARCHAEOLOGICAL REMAINS OF THE SEVEN PREVIOUS CHURCHES THAT TAKES THIS SITE BACK TO THE 2nd CENTURY A.D., TO ROMAN TIMES. >> Geller: THEY FOUND LAYERS OF HISTORY. AND AT THE BOTTOM, A ROMAN ROAD ACTUALLY LAID THE FOUNDATIONS FOR ALMOST TWO MILLENNIA OF BUILDING ON TOP. SO TALK ABOUT YOUR LAYERS OF HISTORY RIGHT HERE. IN THE REFLECTION, WE SEE THE ROMAN ROAD FROM THE 2nd CENTURY. WE'VE GOT THE 12th-CENTURY WALL RIGHT THERE. THIS IS THE 11th-CENTURY WALL RIGHT HERE. >> YES, SO IT'S A GREAT MUDDLE, REALLY, OF PERIODS. BUT IT JUST SHOWS THAT THERE HAVE BEEN ALL THESE DIFFERENT LAYERS OF OCCUPATION AND EACH GENERATION BUILDING ON THE RUBBLE AND THE REMAINS OF THEIR PREDECESSORS. >> Geller: BUT THE REMNANTS OF THE ROMANS WERE JUST THE BEGINNING OF WHAT WAS BENEATH ST. BRIDE'S. SKELETONS AND MASS GRAVES WERE UNDISTURBED FOR OVER 150 YEARS, HIDING WITHIN THE WALLS OF THE CHURCH'S CRYPTS. >> COME WITH ME. WE'RE GOING NOW INTO SPACES THAT WERE OPENED UP FOR THE FIRST TIME FOR A COUPLE OF HUNDRED YEARS IN 1953. >> Geller: IT'S YET ANOTHER LEVEL THAT THE PUBLIC IS NOT ALLOWED TO SEE. >> THIS IS PERHAPS ONE OF THE MOST INTERESTING HIDDEN TREASURES DOWN HERE. THEY WERE FULL OF BONES AND SKULLS WHEN THEY WERE FIRST OPENED UP. THIS IS A LATE-16th-CENTURY CHARNEL HOUSE. >> Geller: THIS, UH... I CAN DESCRIBE WHAT I'M SEEING, BUT IT'S HARD TO DESCRIBE WHAT I FEEL. THIS IS A ROW OF SKULLS HERE, AND THAT'S A PILE OF BONES. WHEN YOU LOOK IN THE SOIL, YOU CAN SEE LAYERS OF BONES. >> THEY MAY EVEN GO DOWN BELOW WHAT WE CAN SEE NOW. >> Geller: BUT WHY WOULD THOUSANDS OF LONDONERS BE BURIED IN SUCH A SMALL CRYPT? LONDON WAS STRUCK BY A PLAGUE EPIDEMIC IN 1665 AND LATER RAVAGED BY CHOLERA OUTBREAKS DURING THE EARLY 19th CENTURY. DURING BOTH THESE EPIDEMICS, CORPSES WERE EVERYWHERE, AND THE DEAD WERE PILED HIGH IN MASS GRAVES JUST LIKE THIS ONE. WHEN PLAGUE BROKE OUT AGAIN IN 1854, PARLIAMENT ORDERED THE END TO BURIALS IN THE CITY. SO THE CRYPT WAS SEALED AND COMPLETELY FORGOTTEN. THIS ARCHED ROOM -- WHEN WAS THIS BUILT? >> THE BRICKWORK HERE IS, AGAIN, EARLY 17th CENTURY, ENTIRELY CONTEMPORARY WITH THE BONES. >> Geller: HUNDREDS OF YEARS, THOUSANDS OF PEOPLE HAVE WALKED, AND DO THEY HAVE ANY IDEA THAT THIS EXISTS BENEATH THEIR FEET? >> MOST PEOPLE DON'T. NO, THIS IS A BIT OF SECRET, HIDDEN LONDON, REALLY. >> Geller: WHAT A ROOM. >> 'TIS INDEED. >> Geller: IN LESS THAN ONE SQUARE BLOCK, YOU'LL FIND 2,000 YEARS OF HISTORY BURIED UNDERGROUND. ROMAN ROADS, MEDIEVAL CRYPTS, AND EIGHT DIFFERENT CHURCHES STACKED ON TOP OF ONE ANOTHER. BUT MOST PEOPLE HAVE NO IDEA THIS OTHER WORLD EXISTS. >> WE'RE NOT ALWAYS AWARE, WHEN WE WALK AROUND THE STREETS OF LONDON, THAT WE'RE WALKING ON TOP OF, IN A SENSE, A WHOLE CITY THAT'S HIDDEN IN SUBTERRANEAN PASSAGES AND TUNNELS. BUT WE DEPEND ON ALL THAT FOR OUR DAILY LIVES. AND THERE'S SOME AMAZING TUNNELS AND UNDERGROUND PLACES AROUND THE WIDER PARTS OF LONDON. MOST ALREADY KNOW ABOUT WINSTON CHURCHILL'S LEGENDARY CABINET WAR ROOMS -- THE 3-ACRE SUBTERRANEAN BUILDING LOCATED BENEATH THE STREETS OF THE WESTMINSTER DISTRICT. THE PROBLEM WAS THAT HITLER ALSO KNEW ABOUT IT -- MAKING THE WAR ROOMS A PERFECT TARGET. AT THE DAWN OF WORLD WAR II, SIR WINSTON CHURCHILL REALIZED THE CABINET WAR ROOMS WOULD NOT SURVIVE A DIRECT HIT. HE NEEDED A TOP-SECRET STANDBY LOCATION. THE SOLUTION? A BOMBPROOF ENGINEERING MARVEL 40 FEET BELOW SUBURBAN LONDON. ITS CODE NAME -- PADDOCK. TODAY, ITS LOCATION IS STILL RELATIVELY UNKNOWN. BUT UNDERGROUND EXPEDITIONARY ANDREW SMITH HAS ACCESS TO ONE OF WORLD WAR II's BEST-KEPT SECRETS. ALL RIGHT, THIS LOOKS LIKE QUITE A FORTRESS HERE, HUH? >> IT'S BIG, ISN'T IT? LOVELY, THICK GATES. SADLY, THIS ISN'T WHAT WE'RE HERE TO SEE. >> Geller: THIS ISN'T IT? >> THIS ISN'T IT -- NOPE. WHAT WE'RE HERE TO SEE IS THIS LITTLE GRAY DOOR IN THE WALL OVER THERE. >> Geller: RIGHT HERE? PLACE LOOKS LIKE A UTILITY SHED. >> IT MAY, BUT THIS IS CHURCHILL'S SECRET HIDEOUT. LET'S GO AND GET OUR GEAR ON. OKAY, SO A FEW THINGS WE NEED TO BE CONCERNED ABOUT HERE. THERE'S LOTS OF MOLD GROWTH AND THINGS AND FUNGUS IN THE BUNKER, SO PLEASE DON'T TOUCH ANY OF THAT. AND THE BIGGEST RISK IS FIRE. SO IF WE HAVE A FIRE, MAKE SURE YOU FOLLOW ME ALL THE WAY UP HERE AS QUICKLY AS POSSIBLE. >> Geller: I'LL FOLLOW HIM. >> OKAY, SO LET'S GO DOWN -- WATCH YOUR FOOTING HERE -- THROUGH TO WHERE THE BLAST DOORS WOULD HAVE BEEN. >> Geller: THIS TOP-SECRET LOCATION WAS BUILT IN 1938. WAR WAS IMMINENT, AND THE ORIGINAL CABINET WAR ROOM BACK IN LONDON, JUST 10 FEET UNDERGROUND, WOULD BE DEVASTATED BY A DIRECT HIT FROM GERMAN BOMBS. ANOTHER STRONGER, SAFER BUNKER WOULD HAVE TO BE BUILT. SO THIS TOP-SECRET SUBURBAN LOCATION WAS CHOSEN. HIDDEN 40 FEET BENEATH A GOVERNMENT-OWNED RESEARCH STATION, BRITISH ENGINEERS BEGAN TO CARVE OUT CHURCHILL'S TOP-SECRET SUBTERRANEAN WORLD. IT WAS FROM THIS SITE THAT HE WOULD BE SAFE ENOUGH TO SPEARHEAD THE COUNTERATTACK TO HITLER'S BLITZKRIEG. OH, SURE, THESE ARE THE BLAST DOORS, HUH? >> YEAH, THIS IS WHAT'S LEFT OF THEM, ANYWAY. WE'VE GOT SOMETHING IN THE REGION OF 50 ROOMS DOWN HERE, ALL OF WHICH WOULD HAVE HAD A DIFFERENT PURPOSE. AND IT WAS DESIGNED TO ACCOMMODATE SOMETHING IN THE REGION OF 150 TO 200 PEOPLE -- THE CORE NUCLEUS OF CENTRAL GOVERNMENT. AND JUST HERE, WE'VE GOT THE MAIN POWER ROOM. NOW, THIS IS THE STANDBY GENERATOR. IF POWER HAD GONE OFF, THIS GENERATOR WOULD HAVE BEEN KICKED IN, CONTROLLED BY THIS PANEL HERE, WHICH IS VERY RUSTY AND COVERED IN MOLD. AND THAT WOULD HAVE PROVIDED POWER FOR THE BUNKER. >> Geller: LOOK AT THESE THINGS. THEY REALLY LOOK FROM THE ERA, RIGHT? YOU'VE GOT YOUR AMP NEEDLES RIGHT HERE, YOUR VOLT METERS. AND THIS IS ALL A SELF-CONTAINED UNIT, AND THIS WAS FOR THE ENTIRE BUNKER, WHICH IS A REALLY LARGE STRUCTURE. >> YEAH, YOU COULD RUN THE ENTIRE BUNKER OFF THIS SINGLE GENERATOR. WE'VE GOT A GENERATOR ROOM, WE'VE GOT A MAP ROOM, WE'VE GOT OFFICES FOR THE MINISTRY OF WORKS, AND, OF COURSE, WE'VE GOT THE WAR CABINET ROOM WHERE WINSTON CHURCHILL CHAIRED THE WAR CABINET MEETING HERE IN OCTOBER 1940. THIS IS THE MOST IMPORTANT ROOM IN THE BUNKER. THE MOMENT YOU WALK IN HERE, ACOUSTICALLY IT'S VERY DIFFERENT. ALL THE WALLS WERE COVERED IN ACOUSTIC PANELING SO NOBODY OUTSIDE COULD ACTUALLY HEAR WHAT WAS BEING DISCUSSED IN HERE BECAUSE THIS IS WHERE CHURCHILL HELD THE MEETING OF THE WAR CABINET. >> Geller: SO RIGHT OVER HERE, CHURCHILL IS SITTING WITH ALL HIS WAR MINISTERS THINKING HOW WE'RE GONNA DEFEND OUR COUNTRY AGAINST THE NAZIS -- THE FREE WORLD. YOU HAVE TO DO A LITTLE BIT OF IMAGINATION, BUT YOU COULD SEE THE OUTLINES ON THE GROUND, THAT THERE PROBABLY WOULD HAVE BEEN A TABLE AROUND HERE, RIGHT? AND YOU COULD SEE HOW THE LIGHTS -- THERE'S THIS FAN ON THE SIDE HERE THAT WOULD HAVE ILLUMINATED. SO THERE WOULD HAVE BEEN MAPS OVER HERE, RIGHT? AND THIS WOULD HAVE BEEN IT, RIGHT HERE. >> YEAH, ABSOLUTELY, BECAUSE WE'D HAVE HAD CHURCHILL, CLEMENT ATTLEE, THE LORD PRIVY SEAL, THE THREE JOINT CHIEFS OF STAFF -- ALL SAT AROUND THIS RECTANGULAR TABLE IN THE MIDDLE OF THE WAR CABINET ROOM UNDER DOLLIS HILL. >> Geller: AND YOU'D HAVE NO IDEA. IF YOU'RE WALKING OFF THE STREET, YOU SAW THIS TINY LITTLE PILLBOX AND YOU CAME DOWN HERE, THAT THIS WAS THE SEAT OF THE FREE WORLD. >> THIS REALLY IS A BUILDING OF IMMENSE HISTORIC IMPORTANCE TO THE BRITISH PEOPLE. >> Geller: BUT THIS MASSIVE STRUCTURE WAS ALSO A FEAT OF BRITISH ENGINEERING. MILITARY ENGINEERS DESIGNED IT TO BE 120 FEET LONG AND 40 FEET WIDE. THE STRUCTURE ITSELF WAS 40 FEET DEEP. WHEN IT WAS BUILT, PADDOCK WAS CONSIDERED INDESTRUCTIBLE AND COULD SURVIVE A DIRECT HIT FROM THE BIGGEST BOMB THE NAZIS HAD -- A 500-POUNDER. BUT HOW? THE FIRST LINE OF DEFENSE WAS THE SURFACE BUILDING, WHICH WOULD ABSORB THE FIRST ROUND OF BOMBS. THEN 17,000 TONS OF SOIL AND SAND LAY ABOVE THE SUBSTRUCTURE. 3½-FOOT-THICK WALLS OF REINFORCED CONCRETE PROTECTED IT FROM THE SHOCK WAVES OF BOMBS. THE SUBBASEMENT WAS PROTECTED BY ANOTHER 6 FEET OF REINFORCED CONCRETE BENEATH THAT. AND FINALLY, TO TOP IT OFF, A LAYER OF CAMOUFLAGE NETTING WAS DRAPED OVER THE ENTIRE COMPLEX, MAKING THE OUTLINE OF THE SURFACE BUILDING UNDETECTABLE TO NAZI PLANES FROM THE AIR. >> IT WAS A REAL ENGINEERING FEAT IN 1939, AND IT COST NEARLY A QUARTER OF A MILLION POUNDS IN THOSE DAYS. THAT'S HALF A MILLION DOLLARS -- A<i> PHENOMENAL</i> AMOUNT OF MONEY BACK IN THE LATE 1930s. >> Geller: SO PADDOCK WAS AN ENGINEERING MARVEL, A SUBTERRANEAN CITY OF ITS OWN WITH GENERATOR ROOMS, VENTILATION SYSTEMS, AND TOP-SECRET WAR-PLANNING ROOMS. BUT THIS COMPLETELY BOMBPROOF BACKUP GOVERNMENT OFFICE BUILDING, 40 FEET UNDERGROUND, WAS MISSING ONE THING. SO, WE'VE SEEN THE GENERATORS, WE'VE SEEN THE WAR ROOMS, KITCHEN -- WHERE'S THE CRAPPER? >> WELL, THAT'S VERY INTERESTING. A BIT OF A DESIGN FAULT THERE BECAUSE WHEN THE ARCHITECT DESIGNED THE BUILDING, HE DESIGNED IT WITHOUT ANY TOILETS. >> Geller: NO TOILET IN THE ENTIRE PLACE? >> THERE IS NO TOILET IN THE BUNKER. THE TOILET WAS ACTUALLY IN THE SURFACE BUILDING. SO IN THE EVENT OF THERE BEING A MUSTARD-GAS ATTACK OR AN AIR RAID OR SOMETHING, THE BUNKER BEING USED IN LOCKDOWN MODE -- IT WAS ALL SEALED -- THEN THE SANITATION FOR WINSTON CHURCHILL HIMSELF WOULD HAVE BEEN A FIRE BUCKET. >> Geller: YOU'RE KIDDING ME?! >> NO, IT WAS BOMBPROOF, BUT IT WASN'T WATERPROOF AND IT NEVER HAD A TOILET. >> Geller: GO FIGURE. THE ACCOMMODATIONS IN PADDOCK WEREN'T LUXURIOUS. IN FACT, CHURCHILL HIMSELF WROTE ABOUT HIS EXPERIENCE IN HIS MEMOIRS, CALLING IT A DISMAL PLACE. BUT PADDOCK WASN'T BUILT FOR PLEASURE -- IT WAS BUILT FOR PROTECTION. AND IN THAT, IT HAD SUCCEEDED. THE EVENTS THAT TOOK PLACE IN THIS DERELICT WORLD, HIDDEN BENEATH LONDON'S SUBURBAN NEIGHBORHOOD, ALTERED THE COURSE OF THE WAR. AND LIKE SO MANY OF LONDON'S MOST SIGNIFICANT EVENTS, THEY TOOK PLACE UNDERGROUND. SINCE THE 2nd CENTURY, LONDON HAS BEEN A CENTRAL PLAYER IN THE HISTORY OF THE WESTERN WORLD. IT BEGAN AS THE CAPITAL CITY OF THE ROMAN PROVINCE BRITANNIA AND IN THE WAKE OF AN URBAN ASSAULT UNLIKE ANY OTHER, STOOD UP TO THE FREE WORLD'S GREATEST THREAT. IN 2,000 YEARS, WE'VE ONLY JUST BEGUN TO PEEL BACK THE LAYERS OF LONDON'S HISTORY. WHAT TRACES OF ROMAN LONDON STILL LIE HIDDEN UNDER MODERN HIGH-RISES? HOW MANY LOST RIVERS ARE YET UNDISCOVERED? AS EUROPE'S LARGEST CITY CONTINUES TO GROW, ITS UNDERGROUND HAS NOWHERE TO GO BUT DOWN.
