TOR:R:TO @ >> NARRATOR: High in the Peruvian Andes lies a mysterious lost city. A 500-year-old riddle where ancient engineers moved 20-ton stones and constructed acres of stepped terraces to anchor the city to the mountain. Reluctant to divulge its secrets, the site has puzzled scientists since its discovery in 1911. Now, "Machu Picchu" on<i> Modern</i> <i>Marvels.</i> <font color="#FFFF00"> Captioning sponsored by</font> <font color="#FFFF00"> A&E TELEVISION NETWORKS</font> >> NARRATOR: Perched on a ridge in the Peruvian Andes, 1,600 feet above the river valley below, is the mysterious engineering marvel, Machu Picchu. Here, without the use of the wheel or iron tools, Inca craftsmen constructed a city of stone. The site exemplifies Inca engineering at its best. Designers constructed more than 600 terraces to keep the city from sliding down the mountain. Hydraulic engineers built a half-mile long water delivery system... and masons erected temples incorporating some of the finest stonework in the entire New World. The architecture was particularly significant to the Inca. Built into the surroundings, the temples are oriented to catch the rays of the rising sun. The pitch of the roofs reflects Huyana Picchu, the mountain that towers behind them. But Machu Picchu has closely guarded its secrets... its true identity and purpose concealed for over 400 years. By studying the city's design, construction and principal features, scientists are trying to unlock a few of its mysteries. >> RICHARD L. BURGER: It's a very complex place and, although I think we know much more about it now, there's still a great deal to learn about it. So I don't think in any way we've eliminated all of the mysteries of Machu Picchu. >> NARRATOR: Abandoned in the 16th century and consumed by the Andean jungle, it became a site lost in time and was forgotten about by even the people who built it. Untouched for centuries, Machu Picchu is a window into the past, through which we can see those who built it, the Inca, an ancient civilization that was the most powerful empire in South America. We see the man most likely responsible for its abandonment, Francisco Pizarro, a Spanish conquistador who invaded Peru and ultimately destroyed the Incan civilization. And finally we see Hiram Bingham, an amateur archeologist seeking fame who stumbled onto one of the most significant archeological discoveries of the 20th century. >> BURGER: The idea that someone without really any archeological training could discover both Machu Picchu and Vilcabamba on one relatively short reconnaissance is a spectacular accomplishment. >> NARRATOR: From the time of Bingham's rediscovery in 1911, scientists have labored to solve Machu Picchu's riddles. Who were the Incas who built it and why did they abandon the city? By the time Columbus discovered the New World, the Incas controlled a territory stretching from Columbia to Chile, an area far greater than even that controlled by the Aztecs of Mexico. The Incan Empire was arguably the most powerful society in the New World. Their domination of South America essentially began in 1438 when Pachacuti, a great warrior and leader, rose to power. >> ALFREDO VALENCIA ZEGARRA (<i> translated</i> ): He started a great Inca expansion and had a lot of control with regards to religion, art and government. A lot of people believe he was born to rule a great nation. >> NARRATOR: But beyond his military conquests, Pachacuti also initiated major construction projects-- cities, temples, estates and roads. >> KENNETH WRIGHT: They were master road builders, perhaps some 14,000 miles of roads throughout the Inca Empire they maintained. And they could move large groups of troops from one portion of the empire to the other to control the population. >> NARRATOR: The Incas were exceptional engineers and stonemasons. With surgical precision, craftsmen carved and fitted massive blocks of stone. Even without the use of mortar, Incan walls have withstood the test of time and frequent earthquakes which rock the area. The Andean people were also master gold and silver smiths. >> MARITZA CESPEDES SANTA CRUZ: Here we are in the gold museum in Lima, Peru. We have a lot of artifacts of the Incas and pre-Incas. For the Incas, the gold is so special and the most important metal. >> NARRATOR: Gold represented their principal god Inti, the sun. The Incas and their predecessors crafted exquisite pieces-- ceremonial knives and statues, gauntlets... masks and clothing. Some of the Incan temples were even covered in sheets of the brilliant metal. Unfortunately for the Inca, the object of their affection would also seal their destruction. In the early 16th century, a group of Spanish adventurers set out for the New World. In 1532, Francisco Pizarro and 180 men landed in Peru. (<i> Zegarra speaking Spanish</i> ) >> (<i> translated</i> ): Motivated by different interests, besides the natural interest of men to know new lands and discover new things, they also wanted to obtain some riches. >> NARRATOR: Pizarro was pleased to discover a civilization which shared his affection for gold. He heard stories of the Incan emperor, Atahuallpa, who ate from golden plates and drank from golden goblets. Upon learning Atahuallpa and his army were encamped near the town of Cajamarca, 350 miles away, Pizarro set out to discover if the tales were true. On November 15, 1532, the Spaniards arrived at Cajamarca and promptly invited Atahuallpa to a feast in his honor. The emperor agreed and on the following day, the Spaniards successfully lured Atahuallpa and his accompanying warriors into a confined courtyard, then sprung from the buildings and slaughtered everyone but the emperor. Now a prisoner, Atahuallpa quickly learned to speak a language the Spaniards understood. >> ZEGARRA: He offered the Spaniards a type of ransom, and they filled one roomful of gold and two roomful of silver, as high as his hand could reach. >> NARRATOR: Gold poured in from Cuzco, their capital, but nothing could quench the Spaniards' thirst. Although the emperor made good on his promise, Pizarro eventually executed Atahuallpa and a full scale war erupted. Despite being vastly outnumbered, the Spaniards had armor and firearms. The Incas used clubs and wooden spears. Already weakened by a civil war and a smallpox epidemic introduced by the Spaniards, the main Incan armies were eventually defeated. In the following years, the Spaniards destroyed the remnants of the Inca civilization, leveling temples and other buildings. But, Manco, a member of the royal family, and hundreds of Incas retreated deep into a mountainous area and eventually established a new capital city, Vilcabamba. From the region, they led guerrilla attacks, but it was a fruitless effort. In 1572, after decades of intermittent clashes, the Spaniards found Vilcabamba and executed the last royal Inca. Vilcabamba was abandoned. 400 years later, it would be the search for the legendary city of Vilcabamba that would lead to the discovery of Machu Picchu. "Machu Picchu" will return o "Machu Picchu" w For centuries, Machu Picchu lay hidden from the rest of the world. The Spanish never found the site, and the decimated Inca-- who knew where it was-- eventually forgot. But in the early 20th century, an American looking for adventure found its secret hiding place and made Machu Picchu the most famous ruin in South America. >> BURGER: Hiram Bingham was an explorer, a geographer, a lecturer in history at Yale University. And during one of his trips to South America, he became very interested in the Incas. And one of the issues about the Inca that he was most curious about was the location of Vilcabamba, which was the last capital of the Incas after they'd been defeated by the Spanish but were trying to recapture their territory. >> NARRATOR: Bingham's father and grandfather were both famous missionaries. And he thought, perhaps, through one of his own daring exploits, he, too, could garner fame. In 1911, Bingham departed on an expedition to Peru, to look for the historically significant city of Vilcabamba. In July, he arrived in Cuzco, the ancient Inca capital. Fueled by rumors of great ruins near a agricultural area called Mandor Pampa, Bingham and his small expedition set out to find Vilcabamba. >> BURGER: He was an incredibly lucky scholar, you know. In the 1911 expedition, he was able to go down a route through the Urubamba into the cloud forest, which is a very difficult terrain because of the dense vegetation. >> NARRATOR: A cloud forest is a wet, tropical mountain forest at an altitude usually between 3,000 and 8,000 feet. Fortunately for Bingham, the Peruvian government recently cut a path deep into the cloud forest to increase trade. >> KENNETH WRIGHT: Hiram Bingham, day six after leaving Cuzco, arrived at Mandor Pampa, which happens now to be at the base of Machu Picchu-- a small agricultural area. And he camped near a hut, where an Indian by the name of Arteaga lived. >> NARRATOR: "He said that on top of the magnificent precipices nearby, there were some ruins at a place called Machu Picchu, not far distant from our camp." Bingham didn't believe this to be the location of Vilcabamba, but he wasn't one to pass by any ruin which might be a new find. On the morning of July 24, Bingham, his guide and his Peruvian military escort set out to climb the great mountain. But there was no easy way to the top. For more than two-and-a-half hours, the group fought their way up the mountain, at times on hands and knees through dense vegetation. Close to exhaustion, the team reached a family living at what seemed to be the top of the world. After a short break, a young boy volunteered to take them further. What lay a short distance ahead would capture the imagination of the world and lay the foundation of Bingham's fame. "Crossing these terraces, I entered the untouched forest beyond and suddenly found myself in a maze of beautiful granite houses!" Although centuries of overgrowth masked the true grandeur of the site, Bingham spent the next few hours taking photographs and making a rough map. Around 5:00 p.m., he headed back to camp. >> BURGER: But he didn't fully appreciate how important the discovery was. In fact, he didn't even go back the next day to take his friends to show them what the ruins were like. I think he recognized, at that time, that it didn't really fit the bill for being Vilcabamba, so he was anxious to sort of move on. >> NARRATOR: For the next three months, Bingham explored other sites, but none as impressive as Machu Picchu. He became convinced the site was more significant than he initially realized. Bingham returned to the U.S. with many photographs and the burning question, "What purpose did Machu Picchu serve?" With the help of his remarkable photos, he secured funding for another expedition in less than a year. In 1912, Bingham was back in the lost city, this time with dozens of workers, a bone specialist, a geologist and other scientists. However, Machu Picchu proved protective of its secrets. The team's first objective was clearing the site of overgrowth. Soon, archeologists began excavating. Bingham was eager to find human remains and the possessions they would be buried with. After a frustrating week, the first burial cave was discovered. Then another. Then another. In the end, 100 graves were excavated. Bingham found skeletons, pottery, stone tools and even bronze knives. Bingham hoped the artifacts might reveal something about the purpose of Machu Picchu. After examining the bones, George Eaton, the team's bone specialist, concluded the vast majority of burials were female. >> BURGER: So, Bingham read this account, and he said, "Well, if we have all of these female skeletons, perhaps Machu Picchu is really someplace where chosen women would live." Bingham was familiar with what the Inca called "Virgins of the Sun," certain women picked to live strict, religious lives and separated from men to ensure chastity. Maybe this was a convent for the Virgins of the Sun. The theory intrigued Bingham, but that was just one of his many theories. >> PETER FROST: This is the Temple of the Three Windows, clearly, one of the more important and one of the more sacred areas of Machu Picchu. Hiram Bingham saw this temple and its three windows, and he took that on to a whole theory of Machu Picchu being the origin place of the Incas, with the three windows representing the three caves from which the legendary Ayar Brothers-- the three founders of the Inca Empire-- emerged from. >> NARRATOR: In 1913,<i> National</i> <i> Geographic</i> published Bingham's story and more than 100 of his photos. The account captivated readers, making both Bingham and the mysterious city famous. Bingham later went into politics and became a U.S. senator. Although he had a notable career on Capitol Hill, it was his discovery on a Peruvian mountain that immortalized him. Bingham published numerous books about Machu Picchu, presenting several theories. Was the city the birthplace of the Inca? The last holdout of the Inca? Or a sanctuary for chosen women? Hiram Bingham died in 1956, never learning the truth behind this amazing find. "Machu Picchu" will return, "Machu Picchu" will return, Whoever chose the location of Machu Picchu couldn't have picked a more awe-inspiring site-- or a more challenging one. The city is precariously perched on a ridge between Huayna Picchu and Machu Picchu mountains. It's a 1,600-foot sheer drop to the river below. Designing and building something of such magnitude at this remote location was a monumental undertaking. Thousands of workers labored to clear the site... lay foundations, construct terraces and erect buildings. >> PETER FROST: This is Machu Picchu as the Incas would have seen it 500 years ago when they arrived here from their imperial capital of Cuzco. There would have been thatched roofs on the buildings, but otherwise it would have looked just like this. >> NARRATOR: The city boasts more than 600 terraces... over 170 buildings... thousands of steps... several temples... and 16 fountains. The Inca utilized hundreds of thousands of stones to build their city, some massive. Fortunately, they didn't have to go far to find construction materials. >> FROST: People often ask, "How did the Incas get these stones here to build this city?" And you're looking at the answer. This is the main quarry of Machu Picchu, a massive jumble of white granite, which they used to create this splendid city that you can see behind us. >> NARRATOR: The quality of Inca stonework is legendary. Important buildings exhibit a precision of stone fitting that almost defies explanation. After 500 years, a knife blade can't be inserted between the stones. >> FROST: This is the rear wall of the Temple of the Sun, probably the most important temple in Machu Picchu, and fittingly, the finest wall of the whole site. An extraordinary example of Inca stonework-- beautiful, level courses, each tapering to a smaller height as they go to the top. >> NARRATOR: How did they achieve such precision? What sophisticated tools did they use? They didn't have steel chisels. They didn't even have iron chisels. Remarkably, without iron tools, the Inca used rock to carve rock. >> RUTH WRIGHT: This is a hammer stone and you look at it and you say, "Well, that's just a river rock. Precisely. They used river rocks, the hardest stone they could find. >> FROST: Here's a stone, you see, that was being cut in the quarries. They used hammer stones, very hard river stones, to pound away the rock. Some of the stones that were worked at Machu Picchu were very, very large, and this is a very big hammer stone that must have been used to break off very big chunks of stone. It might even have been used by two people. This stone probably weighs 30 pounds, and it comes from the river, so it must have been hauled up on the back of somebody, all the way up here to... to Machu Picchu. >> NARRATOR: Some of the largest stones used at Machu Picchu weigh more than 20 tons. How were they moved? Architect and ancient technology enthusiast Vince Lee believes he has an answer. In 1998, Lee and several volunteers conducted an experiment with a 13-ton block of marble. The goal was to move the stone up a ramp with a 25% grade, then turn the stone 90 degrees into position, like the builders of Machu Picchu might have. But Lee wanted to do it without using ropes. Earlier tests proved very large rocks could be dragged into place if you had enough man and space for them to work, but in tight corners or confined areas, ropes just didn't work. Lee's theory involved placing the stone on a wooden sled, which would be moved over a wooden track. Using log levers, the volunteers hoped to inch the sled forward. >><i> Uno, dos, tres!</i> >> NARRATOR: With a heave and a groan, the rock lurched forward. (<i> laughter and chatter</i> ) (<i> team shouting</i> ) Without problem, the team moved the block up the incline. Even turning the stone at the top of the ramp proved easy. Lee believes the Inca used the same technique. The most important buildings relied on the precise fit of the stone and their sheer weight to keep them in place, but there is evidence that less important buildings used mortar made with a combination of clay, earth and small stones. Beside the city's stonework, another feature that distinguishes Machu Picchu is the terrace system. The terraces served two purposes: They provided a place to grow crops and they also kept the city from sliding off the mountain. >> FROST: This is a fairly typical terrace here at Machu Picchu. It's about seven feet high, about ten feet wide, and there are hundreds of terraces like this one here, and these terraces are the secret of why this site remains so well- preserved and so intact despite 400 years of neglect under the forest. >> NARRATOR: The Inca built terraces to cope with the 79 inches of annual rainfall. >> KENNETH WRIGHT: Constructing a terrace is what's really important. The terrace starts out with a coarse, rock base, which provides good water flow and stability. On top of these stones, then, would be smaller stones, and then a gravel layer, and then a sand layer, and then on top of that would be topsoil, and the topsoil is oftentimes three feet thick, rich topsoil that has been brought in and artificially placed to form the terrace for crops. >> NARRATOR: Topsoil was most likely brought to the site from the flood plain 1,600 feet below, basket by basket. Stratified construction allowed rainwater to gently percolate down through the terraces. Until recently, scientists only speculated as to what crops might have been raised to feed the city's population. But in the mid 1990s, soil samples proved maize was the primary crop grown at Machu Picchu, along with potatoes and even avocados. In total, Machu Picchu had 12 acres of terraced land within its walls on which to grow crops. Knowing the type of food grown and the amount of land available led to an interesting discovery. >> KENNETH WRIGHT: What we concluded was that the terraces of Machu Picchu could not have supplied more than 55 people with appropriate nutrients. That meant that food had to be imported. >> NARRATOR: Scientists estimate Machu Picchu had 300 to 750 residents. So where did the food come from? >> KENNETH WRIGHT: There's the great Urubamba River flood plain 1,600 feet below, and we know that there was farming down below because of the wide flood plain. >> NARRATOR: The terraces served Machu Picchu better as claws, helping the city grip onto the mountain. Without them, the buildings would have tumbled down the mountain long ago. The enormous construction effort exemplifies just how important the person was who built it. But who had the resources? Who built this Machu Picchu? "Machu P foundations to fountains, terraces to temples, Machu Picchu was a spectacular engineering achievement. But before construction could even begin, someone had to design it. The architects may be unknown, but their plan is revealing its secrets. The city is divided into an agricultural sector and an urban sector. The urban sector, which covers five acres, is further split in two, separated by a large plaza. >> RUTH WRIGHT: At Machu Picchu, the western sector is the major temples and the Incas' residence. The eastern sector was for the visiting priests and family, but it also had the workshops. >> NARRATOR: Inca architects designed Machu Picchu to exist symbiotically with nature and many features accentuate the landscape. >> PETER FROST: This is the main Inca gateway as you come into the city of Machu Picchu, and as you can see, it perfectly frames the mountain of Huayna Picchu behind us. That's not an accident. >> NARRATOR: At Machu Picchu, nature spoke and the Inca listened. >> FROST: The Incas worshipped nature. They worshipped what they called "huacas," um, rocks, streams, springs. The earth was filled with sacred powers, so you can imagine that at Machu Picchu, they found a place which was particularly potent with sacred power, and so the whole area was a "huaca" if you like. >> NARRATOR: To the Incas, there was little distinction between religion and science. Because they left no written records, we don't know exactly what the Incas intentions were for specific buildings, but scientists speculate several buildings served both a religious function and utilitarian purpose. >> RUTH WRIGHT: The one that the tourists are all brought to first is the Temple of the Sun. It's a very special place because it was built around and on top of a very huge rock. This building, which is circular, surrounds the rock and protects it because the rock is what's sacred. The rock is a "huaca" or a shrine. And this particular "huaca" has an eastern window and on a certain day of the year, the winter solstice, the sun comes through that window and the stone or the "huaca" is cut in a certain way so that the sunlight coming through that window is split in half. So, it's a solar observatory. >> NARRATOR: By knowing the position of the sun, the Incas could determine when to plant crops. Perhaps another temple ensured the sun wouldn't slip away entirely beyond the horizon, never to rise again. >> FROST: Well, this is the famous intiwatana-- "the hitching post of the sun." That word is a modern name that's been invented to describe this kind of rock. It's believed that every major Inca site had one of these, but none of them survived. They were destroyed by the Spanish invaders. They speculated that the Incas performed a ceremony here, where they ritually tied the sun to this post to prevent it from moving any further along the horizon at the time of the winter solstice. But, of course, this is still speculation. We don't know, really, what this stone was used for, and it's another of Machu Picchu's mysteries. >> NARRATOR: The Inca revered the mountains and the spirits inhabiting them. They even carved them in effigy. >> FROST: We call this area here the sacred plaza. It's characterized by this tremendous rock behind me, which has been carved to profile the horizon behind it and the mountain. And I think this is the kind of place where speakers may have addressed a gathered assembly. >> NARRATOR: Another gathering place was the open central plaza which separates the eastern and western urban sections. >> FROST: This is a very cramped environment in Machu Picchu. We're on the top of a mountain ridge. There's not much space here. So they managed to incorporate a fairly large chunk of ground where people could walk around in. >> NARRATOR: The open plaza, the grand temples and the fine stonework made Machu Picchu a city fit for a king-- and maybe, that's exactly who it was for. One collection of impressive buildings might offer a hint. Hiram Bingham christened them "the king's group." >> FROST: So here we are in the king's group, the royal palace. Beautiful stonework, as you can see. One of the features that drew Hiram Bingham to the theory of the king's group, or royal palace, are these big, big, massive lintels, which are the biggest of any residential kind of building in Machu Picchu. >> NARRATOR: Each lintel weighs about three tons and the Inca raised them without a crane. The building is also next to fountain number one. The resident of the king's group had first access on the water, indicating this person was important. The water delivery and drainage system is one of the most impressive engineering works at Machu Picchu. Inca designers routed water from a spring a half mile away into the heart of the city, and delivered it to a series of 16 fountains. The rushing water mimicked the roar of the sacred Urubamba River below. >> WRIGHT: Without water, it wouldn't have been built. It was absolutely essential. The planning started with development of the spring on the north side of Machu Picchu Mountain. >> NARRATOR: From the spring, a 2,450-foot long stone-lined canal carried drinking water to the fountains. >> WRIGHT: The location of the spring, coupled with the law of physics governing the slope at which water runs appropriately in a small canal, meant that the site of fountain number one was predetermined by nature. >> NARRATOR: Two of the most important buildings, the Temple of the Sun and the royal residence, were built adjacent to fountain number one. Therefore, the layout of the city may have been partially determined by the location and elevation of the spring. The sophisticated hydraulic system is not only a testament to the genius of Inca engineers, it also helps answer questions about the people who lived there. In the late 1980s, after 80 years of speculation, the mysteries of Machu Picchu were about to be revealed. >> NARRATOR: "Machi Picchu" will Since Hiram Bingham rediscovered Machu Picchu in 1911, the site has been shrouded in mystery. But Bingham had several theories which endured for decades. Was Machu Picchu the birthplace of the Inca? Or Vilcabamba, the last Incan refuge from the Spanish? Or could it have been a sacred center for the Virgins of the Sun? In the last 20 years, a dedicated group of scientists have labored to find answers. Today, the cloud of mystery surrounding Machu Picchu is beginning to dissipate. In 1983, Richard Burger and Lucy Salazar, anthropologists at Yale University, started reexamining the artifacts of the Hiram Bingham expeditions. The artifacts, most of which had been locked away for 80 years in the basement of the Peabody Museum of Natural History at Yale University, began to reveal surprising information about Machu Picchu. >> LUCY SALAZAR: For example, here what you see is a jar, with two vertical handles. This jar particularly belongs to a group named Collas. This ethnic group was conquered by the Incas and brought to Machu Picchu. They were very famous for their masonry. Machu Picchu probably was made by the Collas. >> NARRATOR: The Collas predated the Incas and were superior builders. Before being conquered, they controlled Lake Titicaca on the Peruvian/Bolivian border. >> SALAZAR: Looking at the materials, the artifacts, the tools, we came to the conclusion that these people were very specialized craftsmen from different parts of the empire. >> NARRATOR: Had the Collas built the city to be the last holdout of the Inca, the fabled Vilcabamba? In the early 1960s, American adventurer Gene Savoy answered with a resounding no. Savoy correctly identified the real Vilcabamba, at a place called Espiritu Pampa, or "plain of the ghosts," 50 miles northwest of Machu Picchu, while retracing Bingham's 1911 expedition. Ironically, Bingham had found Vilcabamba in 1911. He just didn't know it. The site Bingham discovered was so overgrown, he couldn't see the hundreds of buildings the forest concealed. Furthermore, reexamining the artifacts indicated construction at Machu Picchu probably began around 1450, 80 years before the conquest. Then did the Collas build Machu Picchu to be a sacred center for the Virgins of the Sun? With modern forensic tools and 20 years of practical experience, forensic anthropologist John Verano put the myth to rest when he reevaluated the skeletons discovered by Bingham. >> RUTH WRIGHT: They found out that, in fact, there were men and women, that many of the women had borne children, and that myth just didn't fit anymore. >> NARRATOR: So, what<i> was</i> Machu Picchu? For centuries, the answer lay buried in a Cuzco archive. In the late 1980s, Berkeley anthropologist John Rowe was analyzing 16th-century records, when he discovered a group of legal documents that made reference to a royal retreat called "Picchu." Relating it to known sites, the retreat called Picchu looked to be referring to Machu Picchu. >> BURGER: In this document, it says that those lands-- lands around this place called Picchu-- belong to the lineage of Pachacuti, the greatest of all of the Inca emperors. These were documents that had been generated by a legal case in which descendants of Pachacuti were asking for the return of lands that belonged to them. >> NARRATOR: The theory made sense-- a royal retreat built for Pachacuti. New evidence suggested construction began during his reign. >> BURGER: Pachacuti really created the Inca Empire. He had the power necessary to bring the most talented people of the time and basically unlimited labor, and then create a masterpiece to sculpt a mountain and produce some of the finest architecture that the world has ever seen. >> NARRATOR: The legal documents and other facts helped convince Rowe Machu Picchu was a retreat, or country palace. The site was a few days walk from Cuzco, and emperors were known to own royal estates. At an elevation of 8,000 feet, Machu Picchu is definitely a city in the clouds, but surprisingly, it lies 3,000 feet lower than Cuzco, which is 11,000 feet in elevation. Pachacuti could have escaped the cold winters of Cuzco by traveling to Machu Picchu, where it would have been warmer. The new description of Machu Picchu as a royal retreat doesn't diminish its mystical qualities. >> FROST: I believe that Machu Picchu was essentially a sacred religious site that the Incas constructed because of this location. We have to remember, Pachacuti was a religious spiritual leader, not only a political leader. So, it fits with the concept of this being a private estate of Pachacuti that was also an important sacred center. >> NARRATOR: The general consensus today is Machu Picchu likely had a population of 300, swelling to 750 if the Emperor and his entourage were in residence. The site was inhabited from 1450 to 1540 and ultimately abandoned. >> FROST: Perhaps it was the Spanish conquest itself that caused people to leave this place. When the Spanish conquered Cuzco, the people living here at that time would have been Pachacuti's kin group, or what they call his<i> panaca.</i> So, it could be that those few remaining people of his kin group felt too isolated here, they didn't have the means to sustain themselves, and they left. >> NARRATOR: The craftsmen, brought from all parts of the empire to build the city, probably packed up and went home as well. War, famine and a smallpox epidemic wiped out more than 300,000 Incas, helping to erase the memory of Pachacuti's grand estate from the memories of the privileged few who would have known of its existence. The jungle took care of the rest. >> FROST: In the cloud forest region, the vegetation grows extremely fast. The people who maintain Machu Picchu today have a constant battle to keep these terraces clear of vegetation. Within a few years of this place being abandoned, it would have been invisible. It would have been covered with trees. >> NARRATOR: Today, the only thing covering the site are tourists. Each year, more than 300,000 people come to experience the majesty of Machu Picchu. >> BURGER: The awe people feel when they visit Machu Picchu is, in a sense, an appreciation of ancient Peruvian culture. >> NARRATOR: Machu Picchu is one of the last surviving links to a great vanquished civilization. Its people reach out from the mist and point us toward a better understanding of who they were through their remarkable technology. Machu Picchu is a symbol of an emperor's power and a sacred bridge between mankind and nature. >> FROST: Modern science and modern research has answered many of the questions that have puzzled people in the nearly 100 years since Machu Picchu was discovered. And yet, it remains a mysterious place. We still ask ourselves why the Incas were prepared to go to such lengths to build this city here in such a remote location. We don't know the answers to all of those questions. Machu Picchu still is something of a mystery, and perhaps it always will be. <font color="#FFFF00"> Captioning sponsored by</font> <font color="#FFFF00"> A&E TELEVISION NETWORKS</font> Captioned by <font color="#00FFFF"> Media Access Group at WGBH</font> access.wgbh.org
