This is an incredible scene. there's really no other way to describe it than to say it's a scene of mass death.A single family frozen in time.Buried in seconds, almost four, zero years ago.A lot of people refer to this as China's pompeii. could this tragedy hold clues to the collapse of one of China's very earliest ancient kingdoms?I'm Alan maca, an archaeologist and expert in ancient civilizations, and I'm investigating China's distant past from a whole new perspective space.Today, state of the art satellites see the world in stunning detail and reveal hidden archaeology.Enabling us to recreate a lost ancient world invisible to the naked eye.Working alongside leading Chinese experts, my team and I are traveling to some of the country's most remote and incredible landscapes.And with cutting edge science investigating previously unknown cultures, lost cities and devastating cataclysms.This is ancient China as you'VE never seen it before.Three hundred miles west of Beijing in China's Shanxi province and on the edge of barren desert are the hills of the lus plateau. I'm here to explore a revolutionary new discovery that's completely rewriting the earliest history of china.This is shiimauo.A four zero year old citadel at the heart of a lost ancient kingdom.Nothing prepares you to see this place in person.This is one of the greatest new discoveries in the archaeology of the world. this was clearly a massive, massive city.The significance of this discovery became clear just a few years ago. shimao may have been the biggest city of its time anywhere on the entire planet.And Chinese archaeologists are only just beginning to reveal its secrets.Now, with new technology, I want to explore this extraordinary ancient society who congratulations, what's behind its most chilling discoveries? I can tell that some of the bones are very young, and can the fate of China's other lost civilizations help me solve one of the greatest mysteries of all? I feel like I'm in the presence of something otherworldly.WHY, after five hundred years of living here, did the people of this great city? seemingly.Just vanish.Before this discovery, this was just a grassy hill. the only sign of anything man made was a simple line of rocks. when they first found this, they thought it was a part of the Great Wall. you can see why. so they began some excavations around here and they found no, this is two zero years earlier than the earliest phase of the Great Wall.These walls are incredibly well preserved, yet they're over four, zero years old.That means s. shemau is built at the same time as stonehenge in Britain and thrived more than two zero years before the Roman empire.I'VE been to a lot of ancient cities, you don't actually feel like you're in a city because they're ruins, but this and this place, I feel like I am there.This would be an extraordinary discovery anywhere but to understand why this is so groundbreaking.We need to see it from space.The steps structure at the center of the city is built into a hillside high above the meeting point of two rivers.It's in dusty, rugged terrain that borders the sparsely populated ordos desert. experts never expected to find a major ancient city here.It was long thought that Chinese civilization began much later and hundreds of miles to the south in the fertile plains of the yellow river.A stone walllled settlement is totally unexpected at this time period in this place. now I want to know what kind of society built something so large and so sophisticated.I'm lucky to have been invited to explore the latest discoveries with Xiao jing.One of the lead archaeologists at shemal.This is the path up to the giant central platform.This is an immense amount of labor here. this is not rammed earthth, this is not mud brick, this is stone that had to be brought up here to the site it it looks like nothing I'VE ever seen because it's the first time in the history of a Chinese archaeology weve found a four thousand year old structure built this way.I know that I had never expected to see anything like this, but it's, uh, it's amazing to hear that you all had never expected to find anything, uh, this far north at this time.This vast stepped structure is at the center of the city. the team is currently excavating the remains of buildings that once stood at the top.They're trying to figure out how this society worked. this is the top of the giant central platform. the whole area covers twenty thousand square meters. in this prosperous city. the high class people would live here. it included the king's palace, his administration, and large scale artisans workshops. okay, so all of the elites were here living, working. the king was here.음.From the latest excavation data, we can recreate what s shemal might have looked like four thousand years ago.A series of stone platforms with restricted access to each higher level.Right at the top, the palaces of the city's rulers.There's clearly a well defined hierarchy here in this huge structure. this palace dominates the entire area, it's visible for miles, so this thing is a constant reminder of the power of the people who governed here.One of the crazy things is is that archaeologists have only excavated a fraction of this, which makes me wonder how much is out there in the surrounding area. Chinese researchers are discovering ruins spread all over the rugged terrain by combining drone sensing with excavations. now my Tech specialist Ryan kasner and drone pilot William Luo are going to create a photogrammetry model so I can understand just how large this city was. ideally what we want to do is we want to pop it up okay and we want to try to see where the wall is going.My team engineer Eric Lowe combines thousands of images to create a three d view of the terrain called a digital elevation model or deem. so let's have a look at the data. so these are the three multi spectral flights that we did this morning.And then we can see hints of the wall here, but let's switch over to the dem so we have a bit of clearer view. it's a lot easier to see on this home. so we can see the wall we were focusing on right on the ridge, which makes a whole lot of sense. the three d reconstruction clearly brings out the remains of a city wall that follows the ridge line.In all, six miles of these walls have been identified hidden in this landscape. they mark out an enclosed inner city, and an additional ring of outer walls surrounds a thousand acre site, an area the size of about two hundred new York city blocks.That means that four, zero years ago, this could have been the biggest city on the planet.The scale of this place is unprecedented, but even the smallest artifacts being found here are transforming our understanding of how civilization develops in China oh, this is a lot of material here, you guys have been busy! this incredibly fragile jade scepter is a symbol of power carried by rulers of shimu ah, it's very light, it's very lightweight.It would sit on a stuff, right? it' it's amazing to me how thin.They could cut it. I mean you can see, you can see my hand behind here in the light PAR only the song of the god, the emperor held this. he held this to pray to the god, to tell the god that he was the rightful ruler.This is the earliest example of a jade scepter ever found. even the most ordinary looking objects are groundbreaking.These burn holes show that these are what's known as auracle bones, a means of divining the future.The very first Chinese writing will later appear on just this kind of fortune telling device, and one crucial find gives its name to an entire age of human development bronze. this is a knife.This would have been the edge! oh, so should we only have a few dodges? yeah, go ahead! these dated to around the two thousand bc! sure, they are some of the earliest bronzes ever found! wow! this is incredible! all these amazing fives are revealing that many of the foundations of Chinese civilization appear here at shemao centuries earlier than anyone ever expected.But the team has just made an astonishing discovery like nothing ever seen in China before.I'm one of the first outsiders allowed to see it. this is a very important discovery. the people of shima have left us a gift from four thousand years ago.wow.Archaeologists excavating the ancient megga city at shamal.Have just discovered incredible four zero year old carvings in the central palace area.Congratulations! this is unbelievable! this looks like like the ancient Maya city of copan in Honduras from the sixth century ad, two thousand five hundred years later, as an archaeologist, does it get better than this? what not that I know of.There are faces that look half human, half animal.Strange hybrids and familiar creatures are all carved into the walls of the giant platform.It's a unique insight into the beliefs of the people who built this city.These sound the images of people, they are all representations of gods.This is amazing and that there's and that there's also such variety so for example like what, what is this.Mean it almost looks like maybe some kind of a sea creature. this is similar to a find called the green pine dragon from a to city, the home of a later dynasty, the shah.This later dynasty of the central yellow river plains was thought to have founded Chinese civilization, but s. shemao is rewriting history.So far, the team here have excavated just one side of the giant central platform.Much still remains buried.But already the skill and complexity of this lost society is vividly emerging.The carved stone facades of this building are incredible. I mean this is four thousand years ago and and you'VE got images of gods, images of animals like snakes, you even have a dragon which becomes a formative symbol in Chinese dynasties.Everything about s. shemau is more advanced, much earlier and far bigger than anyone thought possible.And all in this unlikeliest of places yet there is a huge mystery here.Archaeologists have dated artifacts found here to between four thousand three hundred and three thousand eight hundred years ago, but after that there's nothing. this means that after five hundred years of occupation, the entire city of shemu seems to be abandoned. something happened here that forced these people to relocate or wiped them out entirely.The question is what?I'm heading across China to see if the latest discoveries about the collapse of other ancient societies can offer clues to what happened at shamal.First I'm heading to the mountainous upper reaches of the yellow river, to the site of an ancient apocalypse.This horrible event took place three thousand nine hundred years ago, but being here and seeing it myself, there's an immediacy like this just happened.The village of lagja was home to a thriving early bronze age community that developed at the same time as shimal. there's at least fourteen individuals here. they all died at once.You can see women with their children as young as perhaps two or three or four years old huddled together around the cooking fire, and clearly this was a family.It's clear to me that the people here had no time whatsoever to get out. all they could do was huddle the young together and hope and pray that they would survive.This frozen, cataclysmic moment has been compared to pompeii near ancient rome.But this family is not entombed in volcanic ash, but thick mud.This is such a striking moment of death here at logja.This adult protecting the child from harm while seemingly looking up what happened here.Archaeologist yeim mao Lin and his team first discovered the bodies, and they'VE spent years trying to piece together how this tragedy unfolded. and they'VE found a vital clue. look at the big crack here. it's from an earthquake.A crack this big shows how powerful the earthquake was either.Okay, wow, so this whole, this whole thing is just completely cracked open.The massive earthquake demolished these houses, trapping the families, but these people are buried in mud.Where did it come from?The latest Chinese research suggests the earthquake triggered a cataclysmic chain of events.I'm investigating what happened to an ancient village known as China's pompeii that left its people buried in mud and frozen in time.The answer could be visible from space.Even after almost four, zero years.My team's satellite archaeologist Sarah klassen, is looking at data from a mountainous gorge twenty five miles upstream from lachja. she's been told about a mysterious GAP in a mountain ridge overlooking the yellow river.There's this one large area that looks like it's been erased, it's almost as though someone's come through and wiped it off the landscape.What we're looking at here is actually a landslide.The devastating earthquake that hit logja would have set off landslides across a huge area. some experts believe one of them buried the people of laja in mud.What the latest research suggests a new theory that this landslide further upstream was so massive that it set off a chain reaction that led to disaster on a biblical scale.To understand what happened, I'm heading high above the gorge geo archaeologist Wu Ching long believes the landslide caused one of the biggest disasters ever to hit China and that it's linked to a phenomenon known as a quake lake. the landslide happened over there. we can see there is a huge part missing from the bridge. at the end of the neolithic period, there was a terrible earthquake here. it was so destructive that this entire ridge fell down panha and the rocks blocked the yellow river.The massive shockwaves send an entire mountain tumbling into the gorge, creating a two hundred meter tall dam across the river.Its remains are still visible nearly four zero years later.The dammed river begins to form one of the biggest quake lakes ever discovered.Doctor Wu calculates that after several months it would have stretched fifty miles upstream.Holding over twelve billion cubic meters of water.The pressure builds as the waters continue to rise.Until the dam breaks.Within twelve hours, ninety percent of the water burst out.That's insanely fastst as a catastrophe, no question, yeah.If doctor Wu is right, this is one of the biggest freshwater floods ever studied and bigger than any in China's recorded history.It would have broughtught devastation for hundreds of miles downstream.So back at shamal, might this city have been hit by a similar cataclysmic natural disaster?The city is surrounded on two sides by rivers, but it's hundreds of feet above the valley floor, which rules out catastrophic flood. what about an earthquake? devastating quakes have struck China throughout its history. one of the deadliest of all time ravaged this part of China five hundred years ago.But shimao's amazingly preserved walls show no sign of earthquake damage.So what did happen here?I'm heading to investigate the disappearance of another remarkable ancient civilization six hundred miles southwest in Guang Han in Sichuan province.Thirty years ago, a discovery was made here that stunned the world.I'VE been given special access to one of China's most extraordinary archaeological treasures. incredible.Could this amazing find help answer the mystery of what happened at shamau?I'VE been allowed privileged access to an amazing relic of an ancient Chinese civilization that I hope could hold clues to the abandonment of shamau.When I see this, when I'm confronted with this, I feel like I'm in the presence of something otherworldly. this astonishing bronze mask is evidence that there was another completely unknown Chinese civilization that existed about five hundred years after shemo. this is like nothing else I have seen in China, and when this was found, this was like nothing anyone had ever seen in the world.It's just one of a treasure trove of precious objects found at the site of an ancient city called sanang shunwe.There are scores of giant faces, striking bronze heads with golden masks.And human like sculptures performing mysterious rituals.I just can't believe how many bronze objects there are and the variety is extraordinary.The world's leading expert on sang shin de believes the giant mass depict gods and the bronze heads represent the rulers of the city.Indu we found many bronze heads in Sha xindui, but we can divide them into two types yo some of them have long braided head yo and some of them don't.the.Professor sun believes these masks, with two distinctive hairstyles represent the two different clans who ruled the city, and his theory could help answer sung Shun Di's most puzzling question.Just like at chimao, the city seemed to suddenly disappear.The clue to what happened lies thirty miles south in Chengdu, the site of another ancient city called jinsha. it emerged around the same time as sunang shue's demise.And archaeologists have found hundreds of objects here, evidence that the two cities belong to the same culture.But professor sun believes there's one crucial thing missing archaeologists here have only found figures from one of the two clans, those with braided hair.De the people who had braided became the rulers of Jin Sha so what happened to the people that had no braid? the people with their hair pinned up? jee what a twitterdu! my theory is that at the end of sshdu there was a great conflict between the clan without bras and those with bras fastened, and the whole city was destroyed.Professor sun's theory of a city torn apart when one clan destroys another in a violent civil war would explain why sun shunhei was suddenly abandoned.So could something similar have happened at shemal?It seems possible because excavations are uncovering grisly evidence of brutal killing.Wow, look at this.It's just heads. yeah, looking at the skulls, I can tell that some of the bones are not yet fused so it they're very young teenager teenagers. yeah, okay.You can tell these heads were cut off because on many we found the incision marks here, but these are not the victims of a power struggle within the city examination of the skulls shows they're all young women.And chemical analysis of their teeth reveals they're not from here, but from more than a hundred miles away to the north.So how did their remains end up here?It could be because shima was involved in some violence, like wars with other territories.It seems these young women were captives, victims of human sacrifice.It appears to be gruesome evidence of conflict with a rival enemy kingdom.So could shimao's downfall have been caused by war?I'm investigating the abandonment of the colossal ancient city of shemau.There's no evidence here for the natural disasters and internal conflict that destroyed other ancient civilizations.I want to know could war with undiscovered rival kingdoms have caused its downfall?To find out, I'm going to analyze the city's defenses and investigate if they were ever breached. starting with the main gateway through the city's outer wall, the formidable east gate, my Tech experts Ryan kasner and Eric Lowe are using laser scanning called lidar to reveal its structure.So what the lidar is going to produce is a three d model that we can move around, look at from different angles and take measurements of as if we had it in real life, but we can do it on the computer you guys? yeah, got some good stuff to show you ben. all right, uh, east gate. yeah, so we'VE been lightering uh, around the east gate past couple days. we're able to scan the entire thing. wow. yeah, this is a combination of about one hundred different scans.The scans reveal advanced defenses.The outer walls include bastions, protrusions at regular intervals that allow archers to fire on the flanks of an enemy attack.And the gateway itself is also ingeniously designed. this is the main entrance to the gate here, but the entire structure is built on the edge of a steep cliff.Now, if an invading army had managed to climb all the way to the top of the cliff, they're confronted first by this u shaped structure, which means they're going to have to divide their force to get in through the gate entrance. and what would be waiting for them here? probably hundreds of soldiers as the first line of defense, the main gateway is protected by guard houses and two massive towers overlooking an l shaped passageway. it forces attackers through a right angled turn and into more concealed defensive positions.And these fortifications are just protecting the outer city. there's a further inner wall and a mile of jagged terrain to cross, even to reach the towering walls of the palace area itself.There's something fundamentally important about the idea of defense at tremont. the city was prepared for an attack on a massive scale.ừ.But archaeologists have found no evidence of destruction or any sign that these magnificent defenses were ever breached, so war did not destroy this city. but perhaps there's just one more possibility that might finally explain shimal's downfall.My team archaeologist Sarah klassen is heading eight hundred miles southeast of shimu to the Yangtze river delta.She's investigating some recently discovered ancient structures that succumb to a final destructive force. she starts by examining a digital elevation model, or dem, a relief map made from multiple satellite images.With the DM, I'm looking for things that you wouldn't necessarily expect to see in nature because it's too, too perfect or too engineered to the north up here, this is really interesting. there are two kind of linear embankments with a depressed area in the middle.Archaeologist Wang Ning Yuen leads a team revealing that these banks are ancient man madede earthworks.Oh wow, you can really get a sense of how big this feature was and how many people would have been necessary to build it.From there to there, it's about a hundred meters across.This massive earth wall is built between two hills to create an ancient man madede dam and reservoir, and from the satellite data Wang Ning Yuan's team have discovered this is just one tiny part of a massive water control system.Miles of artificial waterways that provided transport and control of agriculture over an area nearly twice the size of Manhattan island. amazingly, the ongoing excavations here have dated this to over five zero years ago. it's the oldest evidence of humans harnessing water ever discovered.Chinese experts believe it allowed an earth walled city of more than thirty zero people to flourish in these flood prone coastal lowlands. that means that this new discovery, called liangqu, is the oldest city ever found in china.But like shimo, this city was also abandoned after eight hundred years, and here the latest excavation is finding evidence of why.In my quest to find out why the ancient stone city at shemal vanished three thousand eight hundred years ago, I'VE ruled out the earthquakes, floods and wars that destroyed other ancient civilizations.But Sarah's investigating one more possibility.She's looking for answers in the demise of the oldest city ever found in china.Here, Wang Ning Yuan and his team are finding evidence that the city's agriculture was hit by an unstoppable force climate change. so the layers below here belong to the final period of Liang. this is all man made. the thick layer on top has accumulated from repeated seawater floods.The team's evidence suggests that prolonged heavy rains destroyed the city's agriculture. dwindling food supplies forced the population to move away, and then silt, left by centuries of rising sea levels, buried what remained. it's amazing that yangchu could support such a big city. but when the climate changed and big floods came, the city was helpless in the face of nature. so the environment forged this civilization, but also somehow decided its end.If a dramatic shift in the climate could destroy a city the size of liangchu, could something similar have happened at shemo?Recent analysis of ancient pollen grains found across northern China reveals that when shimao was at its peak, it was much warmer and wetter. but three thousand eight hundred years ago, just when the city declined, the monsoon weather patterns changed abruptly.This area became drier and colder.The climate change evidence makes perfect sense, and if you look at the landscape and look at the soils, it just doesn't seem like this area could have sustained such large numbers of people in ancient times.This is the best explanation so far for the demise of shemal.That sudden climate change transformed this region into a cold semi desert, ravaging the civilization with famine and drought.All the things that sustained life were no longer possible.And when you'VE got people that aren't satisfied, you get flight and you get abandonment.The people of shamau deserted their once great city, leaving it to disappear beneath the wind blowlown silt.Lost for millennia until now.It's so exciting. these discoveries are changing everything. the where and when of how it all began has typically been lost to the mists of time, but now we have real evidence.Right now, all across China, cutting edge archaeology is uncovering an entirely new chapter in the story of human civilization.Now I'm amazed to learn how these lost cultures have struggled to survive in the face of earthquakes and landslides, floods and war like catastrophes with the power to destroy.It's a reminder that great empires rise and can be wiped out again in the blink of an eye.But what they'VE left behind has laid the foundations for all the wonders to come.New beliefs, architecture, art and hierarchies that would lead to thousands of years of civilization in china.