Original subtitles

They are all that remains of an ancient super city.

A civilization that rose from nothing to dominate a continent.

And then vanished.

These pyramids hold the secrets to a spectacular rise and fall.

Secrets that paint a picture of a lost paradise.

A dark secret.

And a chilling fate.

Why would an entire civilization abandon everything it has built?

After centuries of silence, the pyramids of Teotihuacan have a story to tell.

1500 AD.

The Aztecs, rural Mexico.

It is a ruthless empire.

Warriors hunt for humans to be flayed and sacrificed to the gods.

But among the Aztecs are rumors and legends of a lost city.

A peaceful paradise built by the gods.

One day, myth becomes reality.

The Aztecs come across a vision from another world.

Another time.

A fantastical city.

A city of pyramids.

The ruined city is so enormous, the Aztecs believe

it must be the most sacred place in the universe.

They name it Teotihuacan, the place of the gods.

It was built to inspire awe.

A perfect grid of long avenues.

Massive pyramids.

8 square miles of stone buildings.

An area larger than Imperial Rome.

The Aztecs call the central boulevard the Avenue of the Dead.

And they name the two largest pyramids after celestial bodies.

The Pyramid of the Sun.

The Pyramid of the Moon.

From its rise around one AD until its fall nearly seven centuries later.

Teotihuacan was the largest city in the western hemisphere.

The Aztecs have no idea who built the city or why it was abandoned.

And to this day, it's a baffling enigma.

Something terrible must have happened here.

To turn a thriving metropolis into a ghost town.

All the great pyramid builders of the ancient world eventually faded away.

In Africa, in Asia, in Europe, in the Americas.

But we know why most pyramids were built.

As burial tombs for royalty.

Alters for ritual and prayer.

But Teotihuacan is a mystery.

The secret purpose of these pyramids is lost to time.

Because the pyramid builders left almost nothing behind.

We don't know what they called themselves.

The language they spoke.

Aware their rulers are buried.

They left no books, no writing system, no written history of their past.

For nearly a century, archaeologists have been gathering clues.

More than 900,000 pottery shards alone have been analyzed, numbered, bagged and boxed.

The meanings of many artifacts are open to debate.

But recent excavations reveal a story of the life and death of the city of pyramids.

Teotihuacan is an isolated place in the northern

reaches of a region known as Mesoamerica.

At the beginning of the first millennium AD,

it was nothing more than a dusty village.

More cactus than people.

And then suddenly, almost overnight, the population exploded to tens of thousands.

How did this dusty backwater suddenly become the largest city in the Americas?

One theory, people were fleeing from the fire of the gods.

A horrific volcanic eruption.

A mountain suddenly erupting, lava pouring down its flanks.

Entire towns are buried, rivers are damned.

Farmland is destroyed.

It's an apocalypse.

The wrath of angry gods.

In search of safety, the surviving villagers

flee to what would soon become Teotihuacan.

But the city is a mystery within a mystery.

Why did everyone escape to this place?

There were other sites further from the volcano with better soil, more rainfall.

This is one of the puzzles really for us.

There are other things people could have done if they were fleeing a volcano,

for example.

They could have dispersed into other valley systems in the area.

They could have moved further north and lived in a

much more dispersed kind of settlement system as well.

But they didn't.

And for generations, they worked quite hard, it seems, to

really keep themselves quite focused on one piece of land.

The refugees must have been drawn to this location by something.

Or someone.

A person who took charge in this terrifying time and offered survivors a plan.

There might have been a charismatic leader who organized this refugee population into

creating a new order, a new harmony with the universe and the cosmos.

Somebody with an unusually strong connection to sacred forces, who was

favored by gods and also as an individual with a plan, with a plan of action.

The new leaders' plan, they would make a gigantic offering to the gods.

Out of volcanic rock, the very substance that

killed their families destroyed their towns.

They would build man-made volcanoes, pyramids.

The leader offered a simple exchange, manual labor, in return for safety.

The cosmic scale of the plan must have assured the refugees that it would work.

The refugees began building.

A city and a new way of life are born.

The pyramids usher in a new age, a time of order and hope.

They were built at a time of great optimism, of great utopian vision for the future.

The city was one of the most important cities of the entire Mesoamerican region.

It became a place for pilgrimage.

The city was a holy city.

The city would never again be threatened by volcanoes.

The giant pyramids remaining today are only

grey relics of the glory that was Teotihuacan.

Every wall, every building was covered in smooth white stucco and then painted.

The city glowed red.

Pilgrims came from far and wide to this glorious, magnificent place.

Like Vegas, like the Taj Mahal, like the Eiffel Tower, was built to impress people.

This is the first superpower of the Americas.

A wonder of the ancient world, born of disaster, built by a band of refugees.

For centuries, their achievement would draw

people to live in the shadow of the pyramids.

Until another mysterious disaster somehow destroys the dream.

How did it happen?

The secret lies in the pyramids themselves.

At its height in the 4th century AD, there is no place on Earth like Teotihuacan.

The Egyptian Empire has long since collapsed.

Classic Greek civilization has faded away.

Rome has been sacked by the barbarians.

Europe is collapsing into the Dark Ages.

Teotihuacan is reaching its full glory.

Some of the most important things happening on the

planet were happening right here in Teotihuacan.

The population swells, reaching up to 200,000.

Teotihuacan has no rival in Mesoamerica.

The city controls trading routes from present-day Arizona to El Salvador.

It's just huge, the equivalent of anything in the world world.

It's power extended throughout Mesoamerica.

We have indications that people mutate to pecan from well to the north, at least to

Honduras in the south, and out to both oceans.

To truly understand this ancient megacity, compare it to a modern city, Hong Kong,

London, New York.

Powerful centers of culture and commerce.

Immigrants flock to live in the shadows of their skyscrapers.

Teotihuacan was no different.

People from all over Mesoamerica came to live in the city of pyramids.

Skyscrapers are the pyramids of the modern age.

They speak of power, status, dominance.

But building big takes more than ambition.

It requires knowledge.

How did this ancient civilization build such monstrous pyramids?

It seems an impossible feat.

They had no knowledge of metal tools, or draft animals.

And they didn't use the wheel.

This puzzle has inspired some strange theories about who built the city.

Egyptians.

The lost tribes of Israel, Phoenicians, even extraterrestrials.

All have been proposed as the real builders

of the pyramids, and all have been debunked.

These pyramids, these structures developed right here

by the ancestors of the people who live here right now.

The Teotihuacanos didn't need Egyptian stonemasons

to teach them how to build the pyramids.

They invented their own methods, engineering, architecture,

and the ability to organize staggering amounts of labor.

The

pyramid of the sun alone weighs around 8 billion pounds.

Workers quarried into the earth until the landscape was littered with caves.

They cleared five square miles of topsoil for the dirt interior of the pyramids.

By hand, they hauled the stone miles from quarry to pyramid.

Stone after stone, day after day, year after year.

Generations lived and died to build the pyramids.

This was an epic massing of human labor, rivaling

the greatest construction projects in history.

And it appears this huge labor force was all volunteer.

There is no evidence of slavery.

If you've ever tried to get worked on by force, it's extremely difficult.

They had no large standing armies.

They had no police force.

The only possibility is persuasion.

And persuasion is what it did.

Analysis of teeth and bones exhumed from ancient graves early in the city's history

reveals that workers were relatively healthy.

These people are not building the pyramid because they're being forced to with webs.

They're building it because it's their

responsibility to the state as citizens of the state.

And in that sense, it becomes their pyramid.

It's their construction.

If the workers weren't slaves, someone must have ruled over them.

Was there a king, an emperor, a governing council?

No one knows for sure.

Not a single clue has been unearthed that reveals the name of a Teotihuacan leader.

We don't know for sure where they lived or where they were buried.

Never in the history of archaeology in the city

have we found anything that looks like a ruler.

Flaunting individual power does not seem to have been a Teotihuacan thing.

Almost every other civilization in history has publicly honored its rulers.

The pyramids of Egypt are monuments to dead pharaohs.

The reigns of Maya kings are spelled out in glyphs carved in stone.

The emperors of Rome were glorified as living deities.

Giant marble monuments honor U.S.

presidents.

Many believe the answer to who ruled the city of

pyramids lies buried in the pyramids themselves.

A likely place for tombs of rulers is in the second largest in the city.

The Pyramid of the Moon.

Archaeologist Saburo Sugiyama is digging

deep into the pyramid in search of the tombs.

The work is dangerous.

The tunnel could collapse at any moment.

They move slowly, carefully reinforcing the walls.

At the end of the tunnel he makes an unexpected discovery.

A wall.

Not to a tomb, but to another pyramid.

The pyramid we see today hides an older pyramid.

Sugiyama continues to dig deeper.

And then he unearths another pyramid.

And another.

And another.

We found seven.

A total of seven buildings.

The Pyramid of the Moon is not one pyramid, but seven.

Why build pyramids on top of pyramids?

Sugiyama believes the pyramids were the ultimate symbol of wealth and might.

As Teotihuacan grew to dominate all of

Mesoamerica, the rulers built bigger and bigger.

The message of these giant structures is all too clear.

This land is ours.

We are the absolute power.

We can build as big as the gods.

Sugiyama still believes that someday he'll discover

a royal tomb and reveal a ruler of Teotihuacan.

But there is compelling evidence that the pyramids had another purpose.

An ingenious innovation built into their very design.

The pyramids held the secret to keeping the city alive.

Beneath the pyramid of the Sun is a cave.

From its mouth near the stairway, it runs 330 feet into the heart of the pyramid.

To the people of Teotihuacan, caves were sacred.

Here, the gods are born.

The dead pass to the underworld.

Religious cults come to pray in secret.

This cave may have been so holy that the pyramid of

the Sun was built as a giant vault to protect it.

But there may be a more complex relationship between cave and pyramid.

The tunnel travels in an east-west direction.

The exact orientation of the pyramid.

Is this precise alignment a coincidence?

Or a clue to the pyramid's purpose?

The front of the pyramid points like a giant arrow to a location on the horizon.

Once a year, on this exact spot, a constellation

called the Seven Sisters appears on the horizon.

This astronomical event signals the best time to plant crops.

A good harvest meant prosperity.

A bad one could mean mass starvation.

The survival of the city rested on accurately using the stars to keep track of time.

And the pyramids were built to do just that.

The pyramid of the Sun was a huge alarm clock.

The sky, which is after all the most dependable aspect of nature for us far

better than trying to figure out when the leaves are

going to turn or when the first crocus is going to bloom.

How did they align the pyramids with the path of celestial bodies?

They had rudimentary tools at best.

To actually accomplish it does not require bulldozers, computers, even slide rules,

machinery, calculators, nothing like that.

It's persistent observation over time.

The fate of an entire civilization may have rested on one person and a few sticks.

It was as simple as aiming the sights of a gun.

The astronomer would line up two sticks with the

setting sun or stars to create a straight line.

This line becomes the central axis of the pyramid.

You don't realize what you can do with the naked eye, with the hands, with string,

with ropes.

With sticks.

This simple method allowed them to align the

entire city with the paths of the sun and stars.

Some scientists believe this was the plan from the very beginning.

A city connected to the cosmos.

For the entire life of the city, they never strayed from this sacred design.

When the people of Teotihuacan looked up at the stars, moon,

sun, they believed they were gazing at the gods themselves.

And now, the city was in perfect sync with the daily paths of deities.

Good fortune should befall the land.

And for centuries, it did.

What began as an astronomical observation

developed over time into an elaborate ritual.

Into religion.

In temples on top of the pyramids, the priests prayed for rain, for fertility.

There was a lot at stake in having these rights conducted at the appropriate time.

Would the gods look down on us favorably?

We want to pray for rain, a gentle rain that will nurture the maze crop.

The priests scattered seeds in water and offering to the gods.

A city aligned with the stars.

Peaceful rituals.

The evidence seems to paint a city striving for harmony, for peace.

If so, Teotihuacan was dramatically different

than the other great empires of the Americas.

The Aztecs in the Maya worshipped bloodthirsty gods.

Gods that demanded more than offerings of seeds and water.

They demanded human blood.

Could Teotihuacan have been so different?

A thousand years later, many people would like to think so.

On the spring equinox, people from all over the world

flocked to the pyramids to worship the rising sun.

Many believe the pyramids have supernatural healing powers.

If Teotihuacan was built as a city of harmony and

peace, there should be evidence beyond the pyramids.

In the homes of average citizens.

Archaeologist Ian Robertson and Luis Barba are searching

for the ancient houses of ordinary Teotihuacados.

It's no easy task.

Most of the city has not been excavated.

Five modern towns have been built over what was once the ancient city.

The towns are a warren of small streets.

Even with GPS, getting lost is easy.

Man, it's off in that direction.

There it is.

Let me click on that.

It's up there somewhere.

This area looks pretty eroded, doesn't it?

Not a lot of deposition here, but if you were to dig down you

might well find foundations of rather simple small houses.

It may be in this field south of this house, which is 1815.

So it was two meters.

I mean, we're basically here.

This is the center of the collection track.

Well, too often their quest ends in a dead end.

Artifacts are buried under a road, a wall, a building.

The archaeological treasures long gone.

Despite the obstacles, scientists have uncovered acres of stone buildings,

2000 in all.

These are the homes of the Pyramid Builders.

At a time when most of the people of the world were living in thatched huts,

the citizens of Teotihuacan lived an enormous,

single-story stone apartment complexes.

The apartments were not just for the rich, but for all.

Teotihuacan is the only city in the ancient world

that built permanent structures for ordinary people.

This looks like a kitchen of a lesser family compound.

Maybe the dormitory of the family would have

been here, and we don't know what happened here.

Evidence found in these apartment complexes supports

the idea that the city glorified peace over war.

Nearly every wall was once covered with murals.

While only fragments remain, they are revealing.

It's a person dressed as a jaguar with a head

dress, with feathers, a very beautiful one.

And he's kneeling and with a rattle in the hand and doing this type of thing.

And you see that he will walk towards and go up a temple.

This is a building that is very decorated with feathers and with mural paintings.

The private rituals may have been like this.

There are images of conflict and death, but most often they painted nature,

mountains, trees, flowers, water.

A lush garden of strange creatures.

Had the Teotihuacanos accomplished the impossible?

Had they created an earthly paradise?

Or were the murals nothing more than fantasy?

The answer lies hidden in the heart of the pyramids.

In ancient bones that will finally reveal the true nature of Teotihuacan.

And might hold the key to why this super city, so powerful in its glory,

would end up abandoned by the people who built it.

Deep inside the city of pyramids is evidence of a very different Teotihuacan.

It may not have been less violent than the Maya or Aztecs.

It too has a dark and bloody past.

Saburo Sugiyama has made a disturbing discovery deep within the pyramid of the moon.

Human bones scattered in disarray, emerging out of the dirt.

And this appears to be no normal burial.

The skeletons are decapitated.

Their arms are tied behind their backs.

Something dark and violent took place here.

The find doesn't fit the image of a peaceful utopia.

The bones are carefully boxed and taken back to the lab.

Forensic anthropologist Michael Spence believes he can

read in the bones the story of how these people died.

In the cuts, abrasions, size and shape of

the bones are clues to their life histories.

But the bones are in bad shape.

Unlike the Egyptians, the Teotihuacanos did not mummify their corpses.

The headless skeletons are not much more than dust.

But one of the complete skeletons has a story to tell.

Spence names it 6A.

We can say that 6A was a male.

The ruggedness of the bones and various features of them tell us that.

Spence fits the shattered pieces of the skull together.

The hole in the skull is evidence that 6A died violently.

They sacrificed him by tying him up and then hitting him at least twice.

To preserve the success of the city of Pyramids,

this man's life would be offered to the gods.

6A was not the only one.

Dozens of sacrificial victims have been found.

Teotihuacan was not some paradise of peace and harmony.

There was a price to pay for its success.

The currency... human blood.

The gods in Mesoamerican mythology, they had to be nourished.

And was the fate of humans to have to keep the gods going.

With this discovery, we know now that Teotihuacan

was not a peaceful city that we thought it was.

It's now thought that there were many wars.

The people to be sacrificed were obtained as prisoners of war.

They were taken in battle.

The Teotihuacanos apparently appeased their gods with the blood of the vanquished.

The red of the city takes on an entirely new meaning.

And it worked.

The city thrived for hundreds of years.

But somehow, at the height of its power and influence, something went wrong.

Blood was not enough.

The gods betrayed the city of pyramids.

Everything it had become would be destroyed forever.

How did it happen?

What killed Teotihuacan?

For more than five centuries, the metropolis of Teotihuacan thrived.

And then, sometime around the sixth century, it collapsed.

The sacred center of the city was abandoned.

This is a mystery that haunts those who have wandered among the empty ruins.

The

city had the wealth of a continent at its disposal.

How could it have fallen apart so completely?

It's as hard to imagine as if New York City were suddenly abandoned and left to decay.

Only myths remaining above vibrant and bustling city.

The Pyramid Builder's disappearance is a huge

mystery that can be solved from the tiniest of clues.

Not the pyramids themselves, but Teotth collected from ancient graves.

I've seen situations where theories about the collapse

of ancient civilizations have been thrown out.

Because the Teotth did not support them.

Teotth are one of the best ways to gain insight into the health of an individual.

Strong Teotth translates to good general health.

And the Teotth found here revealed that all was not well.

In the later years of the city's history, health was not as good.

The cause of the declining health, the popularity of the pyramids themselves.

Too many people came to live in their protective shadow.

The city became a warrant of crowded streets

riddled with disease and the stink of sewage.

There was not enough food to eat or water to drink.

Lifespans were short.

There could be a variety of reasons for that.

Failures and food supply could be one.

Another one, a prime urban one, is contamination of water sources.

I believe that a very large city, such as this, with a

lot of debris and human excrements going to the drainage.

It was not a very hygienical city.

The pyramids were too successful.

Tensions ran high.

The city had grown to the breaking point.

This apartment complex housed a standing army, a sign that the rulers felt the need

to protect themselves from invasion, or even from their own citizens.

A schism was growing between rich and poor.

The city's main boulevard, the street of the dead,

was now forbidden territory for common people.

The street of the dead had become highly segregated,

very much in the hands of elite Teotihuacanos.

Then, a final catastrophe.

One, the blood sacrifice in the city's careful

alignment to the stars could not prevent.

Drought, the need for rain became desperate.

The priests even killed infants, believing the tears of babies would bring rain.

Well, people may have asked during this cataclysm, what

was it that caused the gods to abandon us, you know?

Why did they forsake us?

The thing that may have happened is that people

said that the priests were not doing their job.

Scientists once believed that as the city

collapsed internally, it was invaded and destroyed.

But there is little evidence of a power in the region

large enough to invade and defeat even a weakened city.

Teotihuacan must have destroyed itself.

Born from fear of volcanoes, the city would die in fire.

Almost 15 centuries later, evidence is still

visible on the walls of the pyramids and temples.

The fires were so hot, they blackened the stone.

Literally, they killed the temples to say we conquered here.

So no doubt about that, the temple was banned.

Maybe it occurred spontaneously one night during a sacred ritual, a sacrifice.

A plea for rain or food.

One theory holds that the city's residents rose in

revolt and burned the symbols of their former glory.

And now they believed of all their misery, the pyramids.

It is as extreme an action as Americans burning down the

White House, or Catholics setting fire to the Vatican.

A tantalizing clue supports this theory.

There is scant evidence of fire damage in the 2000 apartment complexes.

Angry as they were, the citizens would not burn their own homes.

But another theory is far stranger and even more haunting.

Scientists have found evidence of charred piles of wood in the ruins of the temples,

remnants of large bonfires.

Not the kind of blaze set in a riot.

These were premeditated fires.

The real culprits might have been the very

priests who tended to the gods and pyramids.

The glory days of Teotihuacan were gone.

The project was over.

The system was no longer working.

The seats of power, the secret power, the sacred landscape,

above the street of the dead had to be terminated in some way.

They set the temples atop the pyramids on fire.

They smashed the sculptures of their gods.

The priests severed forever, the sacred bond between the city and the cosmos.

Like smoldering volcanoes, the temples on top of

the pyramids burned, a last message to the gods.

Teotihuacan is dead.

Over time, the people slowly abandoned the city.

Here was a culture that dominated all of the Americas for almost a millennium.

And then it was gone.

It dominated the center stage for so long.

It fell, it collapsed, it changed, but then it left its legacy for all of us to see.

But even in death, the city's influence continued

to spread across the Americas and through time.

This mysterious civilization, once thought to be a paradise on Earth, might have been

the original source for the bloody rituals that later empires adopted.

Teotihuacan's gods became the gods of the Aztecs.

We now know it was no utopia.

But there was no other place like it on Earth.

For the first time in the history of the Americas,

people gathered together to live in a metropolis.

They built one of the most massive sacred sites in the entire ancient world.

It was a glorious experiment that lasted for centuries.

A city that strived for harmony, for border.

This is what's hoped.

This is what people are living for.

This is what they're praying to the gods for.

Yes, they had sacrifice.

Yes, they had war.

But it was not at the heart of their ideology.

We still don't know what they called themselves.

What language they spoke, or where their rulers are buried.

All that remains is the stone, millions of stones.

Colossal monuments to a city and a people lost in time.