"Two thousand years ago, a mysterious and little known people ruled the northern coast of Peru." "They built huge pyramids in the desert, comparable in size to the great pyramids in Egypt." "They were called the Moche." "The Moche were the Greeks of Andean culture, they created an exquisite society." "They built a culture of extravagant wealth and extreme violence." "This was a society obsessed with blood letting, we see it in the skeletal record and we see it in the art and iconography." "Then the Moche simply vanished." "Tonight Horizon tells the story of the rise and fall of one of the greatest civilisations of the ancient world." "It's an epic account of human achievement, natural disasters and human sacrifice." "HORIZON" "The Lost Civilisation of Peru" "The Northern coast of Peru, a remote desert area sandwiched between the Andes mountains and the Pacific ocean." "It's one of the most arid regions in the world." "What geologists call a hyper arid desert." "It's such a hostile environment, everything struggles to live." "Yet there are signs that two thousand years ago something extraordinary happened here." "Dotted across the desert are a series of strange shaped mounds." "Many are so heavily eroded that they look like natural hills." "But close up it's possible to see that they are made up of millions of mud bricks." "They are known as huacas, meaning sacred sight in the local Indian dialect." "These are some of the oldest and biggest man made structures in Latin America." "But as scientists have investigated the huacas they found evidence that this was one of the most remarkable civilisations of the ancient world." "This is a huge archaeological complex made up of a number of different sorts of buildings." "But what really stands out are the huacas." "Over there in front of us is what's known as Huaca del Sol." "It's certainly the largest and possible the most important monumental building in South America." "And then facing it in front of this large mountain is a second and smaller huacas known as Huacas De La Luna." "So what we're talking about here is a complex which would have been one of the most important cities in South America." "These great cities must once have been home to thousands of people." "Today we know this civilisation as the Moche." "Careful mapping of the huacas has enabled archaeologists to reconstruct what they looked like and how they might have functioned." "They were giant pyramids built as a series of platforms." "The Huacas Sol over there seems to have been made up of a number of stages at different levels." "In the centre was the tallest platform and on top of it there were a series of buildings with walls and roofs." "This may have been a spectacular palace complex where the rulers of this lost civilisation lived." "We would have expected to contain a number of large patios, corridors, storage areas, kitchens, and then residential chambers and rooms where the rulers families would have lived." "And we think the lower platforms may have been more public areas, spaces where ceremonies and receptions were held for the wider general public." "Some of the pyramids are richly decorated and may also have been sacred centres." "Yet others doubled as burial mounds." "These were clearly the centres of a rich and powerful people." "As archaeologists explored the pyramids further, they discovered the Moche weren't just great builders, but also great craftsmen." "At sites like this they've uncovered a treasure trove of some of the most remarkable artefacts ever found." "The recent discovery of royal tombs and ceremonial sites dedicated to the Moche Gods suggests that these people had reached a cultural level as advanced as the Greeks and similar to cultures of the Middle East, Egypt and the Mesopatamia." "They have also discovered sensational metalwork and jewellery." "The Moche were pioneers of metalworking techniques like gilding and early forms of soldering." "It enabled them to create extraordinarily intricate artefacts." "This is an ear stud, it's one of the masterpieces of the Moche goldsmiths." "And would have been worn by a Moche ruler." "It's made of gold with bits of turquoise mounted in it, and it contains about one hundred separate parts." "In the centre you can see an image of someone." "In one hand he's carrying a large club, the sort of weapon Moche warriors would have carried when they went in to battle." "Then there is the shield and also a nose swing which actually moves." "We're talking here about some of the most spectacular jewellery ever found anywhere in the world." "This was a society with many of the hallmarks of a great civilisation." "The Moche built great cities with massive monumental architecture." "They had a powerful political and religious elite, and they supported an artistic culture capable of producing spectacular pottery and metalwork." "But then, around 650 AD there is a mystery." "Archaeologists found evidence that the cities had been abandoned and this extraordinary civilisation seemed to vanish in to the desert." "The rise and fall of the Moche raised tantalising questions." "How have they created such a sophisticated civilisation in the desert?" "What kind of society was it?" "And most fundamentally of all what had happened to them?" "The problem scientists faced was that much about the Moche was still shrouded in mystery." "They left no written record and the people today have little knowledge of the distant past." "Then archaeologists came across a new clue out in the desert." "Here they found signs of more Moche construction projects, an elaborate system of irrigation canals." "Mud break aqueducts carried water tens of kilometres, many are still in use today." "This was how the Moche had tamed the desert, brought water to their cities, and grown the crops that sustained them." "But what was still missing was any real insight in to how Moche society worked." "There was however one important set of clues, the Moche left an extraordinarily rich record of images and stories on pots and vessels." "Many appeared to depict every day scenes from the world around them." "But there were others that are more unusual." "They appeared to depicts scenes from an elaborate ritual, a form of battle." "The war that they were fighting, combat that they were doing was a ritual performance and the idea is that one of them should be able to knock down the headrest or helmet of the other one." "If he does that one of the warriors becomes a prisoner." "The scene then seemed to show the prisoner being sacrificed, his throat cut," "and the blood drained in to a goblet." "Once they have cut the throat they would introduce a little tube in to the jugular vein so that the blood was easily flowing in to the goblet." "The idea was to slowly kill them and blood was drunk by that supreme deity." "It was a gruesome scene of human sacrifice." "But was it real or imaginary?" "For many years scientists assumed that the scenes were so grotesque that they must be part of an elaborate mythology." "Then in the mid 1990s there was a discovery which would thrown fresh light on these gruesome images." "In 1995 Canadian archaeologist Steve Bourget started a new excavation at the Huacas De La Luna." "We dug a number of trenches in the ground to see what was there, and found a series of human bones." "It occurred to us almost immediately that this was not an ordinary burial site." "Bourget and his team dug further." "The first bones were surrounded by many more." "We dug an area of about fifteen metres by ten metres and found a whole number of human bodies scattered around." "It was then that we realised we'd found something totally exceptional." "Nothing like it had ever been found at a Moche site before." "Bourget realised that he needed specialised help to make sense of what he'd found." "The man he called in was forensic anthropologist John Verano, a specialist in bone analysis." "Verano still remembers it." "I ran in to Steve Bourget on the street and he says" "John I've got something that will make you want to drop everything you're doing." "And I said well great what is it, and he said I've got you know more bones than you can possibly imagine." "So we went out to the site and they were just everywhere, there was basically a field of skeletons." "Bourget asked Verano to examine the skeletons and try to determine how they had died." "The first thing we started seeing was in the, the neck bone." "We started seeing a series of them with slim slash marks right across the front of them." "These cut marks to get to the bone would have to go through all of the throat basically and some very vital structures." "And so these are not just nicks that would be insignificant, they were a cause of death." "In other words, these bodies have been cut across the throat so violently" "that the knife had cut through to the bone." "But this only accounted for some of the cut marks." "We found cut marks not only on the vertebrae, but cut marks on the long bones." "In the middle of the shaft here, on sometimes the wrist bones, finger bones, basically from head to toe some of these people had cut marks, hundreds of them." "Where the cut marks are located are where muscles attach." "So they weren't cutting at the joints and they were not taking the bodies apart." "What they were doing was cutting deeply and then pulling the flesh off, pulling the muscles away from the bone." "Verano searched for an explanation." "Our immediate thought of course was perhaps cannibalism, where they'd taken the meat off to consume it." "But what I found was they were so careful in their cuts they were removing flesh skin and so on from areas that were so difficult to de-flesh," "I think what they were doing in fact was de-fleshing, taking the meat of skeletons to use those skeletons for a particular ritual purpose." "It was a macabre finding, but it proved that the pictures on the pottery were not depicting mythological scenes." "They were describing a real ritual, or religious ceremony." "Scientists realised they'd uncovered an all too real and brutal world of human sacrifice." "It raised a fundamental question, what in a Moche world was so important it required the sacrifice of young men?" "Was there a clue here about how Moche society work?" "And perhaps even to its fate." "Back at the sacrificial site" "Steve Bourget now found something he'd previously missed." "The first body we found was sitting on a bed of solid mud." "But the big surprise was not that we'd found a layer of mud, what was interesting was that the body was totally encased in the mud." "So the sacrifice appeared to have occurred at a time of heavy rain." "It could have been a coincidence." "But as Bourget dug deeper he came across the remains of earlier sacrificial victims." "These two were so encased in mud they had to have been buried during periods of heavy rain." "Yet the Moche lived in a desert where rain is extremely rare." "When we found the first body trapped in mud we thought straight away that it was probably a one off, an accident." "In other worlds the Moche had just happened to sacrifice somebody during a heavy rainstorm." "We didn't think it was very significant." "But when we found bodies that had been entombed in mud from different historical periods we suddenly understood that some of the sacrifices had been deliberately performed in the rain." "The sacrificial scenes suddenly made sense." "Most desert societies have some form of central ritual to celebrate or encourage rain, the Moche it seemed were no exception." "A regular and predictable pattern of rainfall would have been central to their survival, certainly worth the life of a young warrior." "So what I think was going on was that the Moche used human sacrifice to try to maintain a relationship with their God and keep the natural world in harmony." "These were rituals which they believed enabled them to keep an unpredictable world in balance." "Here was a new insight in to Moche society." "A harsh world had moulded a harsh civilisation, with an elaborate set of rituals designed to ensure its survival." "Yet around 650 AD something had changed." "Carbon dating on Moche sites showed this highly sophisticated civilisation had suddenly vanished." "What had gone so badly wrong?" "This was to become the great unsolved mystery of the Moche." "The first new clue was to come from a totally unexpected quarter, hundreds of miles from the Moche settlements on the coast." "In the 1980s climatologist Lonnie Thompson travelled to the Andes." "He was hoping to trace back to ancient times the history of the region's climate." "Here there are glaciers containing ice dating back thousands of years and contained within them is a record of the climate at the time that they were formed." "Thompson knew that by collecting cores from the ice he would be able to read this record." "Each core is made up of a series of rings, each ring showing a different season." "Dry summers show up as narrow rings, dark with dust." "Wet winters, when there was lots of snow, as broader clearer bands." "This pattern is the key to deciphering the climate of the past." "The ice is a beautiful archive because if you look at this you can see if you start on one end of the core you can see the number of years." "This would be a dry season, and from here is to here is a wet season, dry season." "The dry seasons are narrow in the cores and stand out because there's no snowfall." "There would be a lot more dust in this layer, and the wet seasons are broader because that's when you get the heavy snowfall." "This seasonal pattern can be used to build up an annual picture." "Some sections of core consist entirely of narrow dark bands, indicating dry years." "Others have broad clear bands showing wet years." "Almost immediately Thompson and his team noticed something intriguing." "There seemed to be a close relationship between the weather in the mountains and the weather on the coast." "Over the last one hundred years every time the ice core showed drought in the mountains it corresponded to a particular kind of wet weather on the coast." "It's known as the El Nino." "A life giving period of rainfall that arrives on the coast once every five or so years." "The relationship seemed to be clear and consistent." "Dry weather in the mountains meant wet weather and El Nino on the coast." "And the reverse was also true, wet weather in the mountains meant a drought on the coast." "It gave Thompson a powerful new tool." "In theory at least he should now be able to trace back the entire region's climate," "as far back as the Moche." "Armed with this new information" "Thompson and his team set to work, analysing the climatic information in the cores, back through time." "And when they reached the period around 560 AD they found something remarkable." "At exactly the time the Moche began to collapse the weather had gone haywire." "In an early period, starting about 560, 565 and going up to 600 AD we found very distinct annual dust layers and in measuring the dust in the lab we find extreme drought in this part of the world." "Using the information in the ice cores," "Thompson estimated the drought in the mountains to have lasted thirty years." "And if his theory was right it meant that there was an equally extreme but opposite climate pattern on the coast." "This period from 565 to 600 AD corresponds to a major scale El Nino in the coastal areas." "And that El Nino would have been much bigger than anything that we have seen in the last five hundred years." "This would have been something absolutely huge." "It's what's known as a mega El Nino." "You get tremendous floods." "Houses get washed away, communities get washed away." "But there was something else, the ice cores also contained a second story." "Further analysis showed that the years of drought in the mountains had been followed by years of heavy snow." "After the dust event which terminated around 600 AD the annual layer show increase thicknesses which relate to a low period of wet conditions following the drought." "Using his theory that what happens in the mountains is reversed along the coast, it's suggested that the mega El Nino on the coast had been followed by a mega drought." "At least thirty years with no rain at all." "This would definitely have disrupted any type of culture, it would, it would destroy a culture in today's world." "Here was the suggestion of a huge climatic cataclysm between 560 and 650 AD." "The Moche would have been hit by a double whammy." "Even a modern society would struggle under these conditions." "It's the long term changes that really bring about impacts on civilisations." "First one, people bounce back." "Second one, they come back, but they come back slower." "After a while people get really discouraged about having to try to adapt to these changes." "If Thompson was right, all the sacrificial rituals in the world would have been powerless to halt such a catastrophe." "It was an intriguing idea." "But how reliable was it?" "Archaeologists set out to look for evidence of these two epic disasters." "Despite the dryness of the climate all the pyramids show signs of severe rain damage." "If you look over here we found evidence of what looks like major rainstorms going back many years." "Here for example you can see how the walls are gushed down the huacas and formed these enormous gullies." "But if the rain will see them more torrential and penetrated inside the interior, the colour of the building and the mud bricks would fall away in large slabs." "But was this the tell tale sign of a mega El Nino, or was the damage much more recent?" "The frustration was that scientists couldn't tell." "Then Steve Bourget digging at a Moche site called Huancaco made a breakthrough." "The site had been heavily damaged by rain." "When we excavated the site we found new construction work, the town was being expanded." "Then we found evidence that the rain, and not just the rain, but a river of rocks and mud had literally destroyed the new construction." "So this disruption had definitely occurred at the time of the Moche." "But when exactly?" "The new floors and walls had been cut in half by this river of rocks and we could date destruction from organic material left behind." "Bourget carbon dated these organic remains, the result was beyond doubt." "Archaeologically it's impossible to determine exact dates, but we estimate the new construction ceased some time between 550 and 600 AD." "It was the evidence archaeologists had been looking for." "The dates were almost exactly the same as the dates of Thompson's mega El Nino." "Bourget had proved the Moche really had been hit by thirty years of epic floods." "But what about the second part of Thompson's prediction, the decades of drought?" "New excavations at other Moche sites now began to turn up evidence of huge sand dunes." "Many contained artefacts which could be dated." "And they showed that the sand had started pouring in some time around 600 AD, after the mega El Nino." "It could only mean one thing." "At around 600 AD the mega El Nino had been followed by severe drought." "Thompson's second prediction had been verified." "We would have had sandstorms that would have hit the coastal sites and completely covered them." "It's likely that most of the urban infrastructure would have been destroyed." "Here at last was a plausible explanation for the collapse of the Moche." "They had been overwhelmed by an environmental catastrophe." "Thirty years of a mega El Nino followed by thirty years or more of a mega drought." "Everything went wrong at that point, not only the economy, religion, the leadership, even at a personal level people were in a state of complete despair." "It was a total disaster for a society whose religion was based on its relationship with the weather." "The whole belief system of the Moche would have been called in to question." "Young men who until now had willingly offered themselves as sacrifices to the gods must have wondered what the point was." "When a Moche, young elite member died in a ritual sacrifice, he was giving his life, not only to the Gods but also to the state." "So if the elites show their weakness by not being able to prevent the calamity why would people continue giving their work, their labour, their products or their lives." "It was a society that clearly was based on something that was falsified." "The Moche had thought they could control nature, but found they couldn't." "It was a physical and ideological catastrophe from which they never recovered." "It all seemed to fit perfectly." "This became the accepted version of events." "It seemed that one of the greatest riddles in archaeology had finally been cracked." "Then, in the late 1990s American archaeologist Tom Dillehay went to Peru." "Dillehay wasn't interested in the famous Moche sites with their huge pyramids, instead he decided to survey some little known Moche sites in a valley known as the Jequetepeque." "What he found would shatter the established theory." "When we do what we call a complete survey, it's a foot survey and we cover the entire valley, our purpose is to make sure that we find every site, including the large towns and urban cities," "all the way back to farmsteads and even small burial plots." "Many of the sites were so remote they had never been explored before." "John Warner is a member of the survey team." "Warner uses a specially adapted GPS system that maps the terrain he's walking over." "It gives me a diagram, it gives me a map, it plots out where these various features are across the landscape and gives me a fantastic bird's eye view of the relationship of these objects to each other," "from a perspective that I would never be able to achieve just from eye level." "The maps they created show walls, floor plans and street patterns that can't be seen from the ground." "Methodically Dillehay and his team studied artefacts from dozens of similar settlements." "But then they set about dating the sites." "We're able to date most of these sites in the valley through excavation." "What we find are organic remains, food, bone remains, trash, artefacts." "And at a number of sites we're able to place these to AD 650 to 700 years ago." "650 to 700 AD, it didn't make sense." "The accepted version of events was that by 650 AD the Moche had been destroyed in an environmental catastrophe." "This was clearly not true." "The Moche had survived the environmental upheavals." "And fifty years later we're still building new towns, until they finally disappeared sometime after 700 AD." "It was time for some new thinking." "Dillehay's group returned to the settlements." "One of the towns they studied was called Cerro Chepen, it's surrounded by an enormous wall." "The site itself is absolutely huge." "You can see the wall runs all the way around it, it runs all the way around my side over here and far beyond what I can see." "It certainly could have housed hundreds if not thousands of people during the Moche period." "It looked like a massive hill fort, nothing like it had been seen before in the Moche world." "Further down the valley, at a site known as JE125, there was another important discovery." "Well this is really quite interesting here, this is the material that's actually falling off the hillside over here, this jagged stone that breaks in to angular pieces." "It was used to build a lot of the defensive walls and platforms down here." "And yet here we have these well rounded river cobbles, all piled in to sweet little piles along this particular wall." "All placed about two to three metres apart more or less." "The idea being that conceivably one person could stand at each pile, pick up a sling stone, insert it in a sling, swing it about and lob it down in to the valley below." "These piles of stones here represent a prehistoric ammunition." "Until now the Moche had never been associated with anything more warlike than ritualised combat." "But the evidence was unequivocal." "At around 650 to 700 AD, well after the climatic upheaval," "the Moche had been at war." "But who with, and could this explain what had finally caused their collapse?" "We began asking ourselves the question what does this mean." "What does this sudden building of fortresses mean across these valleys?" "Are people fighting with foreign troops coming in from the highlands or perhaps areas to the north of the south?" "The most obvious assumption was that a weakened Moche had been invaded by a neighbouring people." "The first option that came to us was let's try and find more evidence in these sites, do more foot survey and see if we can find any evidence of foreign intruders." "Dillehay and his team scoured the area looking for unusual artefacts that might suggest the presence of a non Moche people." "But there was nothing that suggested any kind of outside invasion." "We started digging more and doing more onsite inspection of the kind of artefacts found at these fortified settlements." "But we saw no evidence whatsoever of any military weaponry they're fighting with, any foreign groups what so ever." "And we discovered that it's very unlikely that foreign intruders brought about this sudden building of the fortresses in the valley." "But if there was no invasion, why the commitment to defence?" "There seemed to be only one other possibility." "Dillehay now pulled together an entirely new picture of what had happened to the Moche." "What we see is a whole series of climatic events, rainfall, flooding," "and drought that's putting stress on the economy." "And all of a sudden it collapses." "And the large ceremonial centres are abandoned and people start warring amongst themselves." "Ritual violence had given way to civil war." "They are competing for the best agricultural lands, the best fishing grounds, and trading partners outside of the valley." "The result was that people began to move out in to the countryside in these fortified settlements to defend themselves essentially against themselves." "It was the Moche's last stand." "A leadership that had failed to protect its people lost control." "These people were playing the last inning of their game, they were playing the last round, their last try." "They have build these temple, they have build these city to prove again that they were able to control nature." "Something that they couldn't." "They were not the great society that they thought or they had been led to believe they were." "They were as weak as any other society." "The Moche had survived rain, they'd survived drought, only to be torn apart by civil war." "One of Latin America's most powerful and long lasting ancient civilisations crumbled away." "Here was a new and much more sophisticated theory for the demise of the Moche." "Yet even this is not the whole story." "The more scientists look the more they realise that in some respects the Moche never completely died." "Today along the coast of Peru it's impossible to escape the legacy of this lost civilisation." "Moche art lives on in the work of local craftsmen." "And if you travel to the highlands the Moche tradition of ritualised combat is preserved in the annual Tinku ceremonies." "Here in a variation of the Moche sacrificial rituals, highland villages conduct ceremonial battles against each other." "The aim is to spill the blood of the opposition, and fertilise the earth." "The Moche I think remained in the memory of the north coast of Peru as the great moment, as their greatest achievement." "They were in a way the Greeks of Andean culture." "Yet only now after fifteen hundred years are the Moche and their legacy finally taking their place in world history."