Original subtitles

It's gigantic.

Why did they build it in this place?

So, there's something underneath us?

[ laughs ] that's stone!

Look at that!

Something just went right by the camera.

Let's see what's down here.

♪

high in the mountains of bolivia and peru

is one of the most intriguing places on the planet --

lake titicaca.

It's the largest lake in south america

and the highest navigable body of water in the world.

And according to legend, it might also have been home

to one of the most advanced ancient civilizations

in the americas.

I'm not talking about the inca, but a far older

and more mysterious culture known as the tiwanaku.

Predating the inca by more than 1,000 years,

they built massive stone temples

that, to this day, have barely been excavated.

The inca believe the tiwanaku

were the first people to walk the earth

and that their capital city was once so massive and so complex,

it must have been built by gods or giants.

They erected bizarre structures with cryptic symbols

that have given rise to conspiracy theories

of alien contact.

And to this day, stories persist

that an even more magnificent city

is hidden deep underwater.

It might sound like fantasy,

but recent scans of their ruined metropolis

reveal it might be larger

and more advanced than anyone believed.

And the discovery of mysterious sunken ruins

has some people saying

that the so-called atlantis of the andes

might actually be real.

So, who built the city of tiwanaku and how?

And is more of their ancient empire really hidden underwater?

A journey to the heart of the world's most legendary lake

might finally lead to answers.

♪

my name is josh gates...

Look! [ laughs ]

...Explorer, adventurer...

That is it!

...And a guy who ends up in some very strange situations.

Ah, ah, aah, haa!

With a degree in archaeology

and a passion for the unexplained,

I travel to the ends of the earth,

investigating the greatest legends in history.

Okay, let's punch it.

This is "expedition unknown."

-- captions by vitac -- www.Vitac.Com

captions paid for by discovery communications

I'm in bolivia to meet an expert on the tiwanaku

in the highest capital city on earth.

[ dog barking ]

[ panting ]

♪

welc-- [ exhales deeply ]

[ breathing heavily ]

forget it. Forget it.

Oh, god.

"welcome to la paz" is what I was going for.

At an altitude of 12,000 feet,

this place literally takes your breath away,

especially since getting around means going even higher.

♪

this is the teleferiqo.

It is the world's highest and longest aerial cable-car system.

It was built a few years ago

to counteract the crushing gridlock down in the city.

And as of today, there are six different cable-car lines,

20 stations, and more than 900 gondolas,

gliding above a sea of humanity.

♪

on the crowded streets below are the descendants of the inca,

aymara natives, and even the enigmatic tiwanaku.

It's a blend of cultures

that makes for some interesting shopping.

Like here, at the witches market...

Hola. ...A one-stop ritual shop,

selling everything from dried llama fetuses,

which is like the local version of a lucky rabbit's foot,

to the unavoidable andean pan flute.

You know, a lot of people don't know this.

I actually took four years of andean pan flute in college.

[ pan flute music plays ]

still got it.

Still got it.

I give the pipes a rest and make my way

to the la paz national archaeological museum.

I've arranged to meet with archaeologist alexei vranich,

one of the world's foremost authorities on the tiwanaku.

Tiwanaku, this is not a household name to most people.

This is not something everybody's heard of,

so, what is tiwanaku?

It's a place up at 13,000 feet above sea level

right on the shores of lake titicaca.

But it's also a people. The people who built it?

The people who built it.

You have this megalithic site.

The scale is so big.

Some of these stones are tremendous.

These stones are so large.

When the first travelers came through,

they referred to it as the american stonehenge.

Wow.

Gates: And much like stonehenge,

tiwanaku is one of the world's greatest mysteries.

Located about 50 miles west of la paz,

tiwanaku was built around 100 b.C.,

more than 1,000 years before the inca arrived on the scene.

The site consists of a large complex of huge stone structures

built near the coast of lake titicaca.

You look at it, and you think, "where did this come from?

Why did they build it in this place?"

it's in the middle of nowhere.

You go there, and there's just nothing,

which has given rise to a lot of wild theories.

The ruins feature cryptic gateways, otherworldly carvings,

and impossibly large walls,

leading conspiracy theorists to claim

the site must have been built with alien assistance.

Even the inca, when they arrived at the ruins

500 years after the tiwanaku collapsed,

were stunned by the size

and perfection of the stonework.

You know, in fact, the inca justification to rule

was based on the idea that they were the firstborn.

The gods made them. They went out to conquer.

Then all of a sudden, they get to tiwanaku,

and they're like, "oh, no.

There's something here that's clearly older than us

and even better." right.

So, what do they do?

They just change their history around.

They said, "in fact, we were born here."

so, the inca suddenly were born at tiwanaku?

They rearranged it a bit and said, "look what we made."

right.

Gates: The precision stonework and massive blocks used at tiwanaku

are more advanced than anything found

in the americas at the time.

So, how did they build this engineering marvel?

You will need to understand what the tiwanaku were

and what the site is like.

You have to go to this one location.

Perfect.

Gates: So early the next morning -- and I do mean early...

...I drive the 50 miles from la paz to tiwanaku...

...To mark a very special occasion.

It's just after 5:00 a.M., and I've arrived at tiwanaku,

a place named after the mysterious people

who once lived here,

so, what am I doing here in the freezing darkness?

Well, to this day, locals believe

that this is the most important moment of the year

in the most important place --

sunrise on the winter solstice.

I'm not alone here.

Thousands of people are descending on this ancient site,

seeking good fortune for the coming year.

Even the president of bolivia, evo morales,

is in attendance,

donning traditional garb

to soak in the first rays of light

at a mysterious stone structure called the gate of the sun.

The tiwanaku believed the sun was created

by a powerful deity known to us as the staff god.

The inca would later call him viracocha.

Legend says he emerged from the waters of the nearby lake,

creating the sun and building the advanced city of tiwanaku

with the help of giants.

All around me are the descendants of the tiwanaku,

and while it might sound crazy, many of them really believe

that this site was built by a god and an army of giants.

But when the sun comes up, it's not hard to see why.

As the first rays of light pierce the frigid air,

thousands of hands are held up to the rising sun...

♪

...And the mysterious city is revealed.

♪

there are sprawling temples, colossal walls, channels,

and stone gutters for water and mysterious carvings.

To find some hard answers as to how it was all built,

I wait for the crowds to disperse

and then meet with leading archaeologist

jose ignacio gallegos

at the so-called gate of the sun.

So, the first thing I notice are these beautiful carvings.

So let's talk about the big guy in the middle.

This is viracocha?

The staff god?

So, he literally comes out of these waters,

and he sort of creates everything?

Gallegos: Yeah.

The really impressive part of this gate, of course,

is just the gate itself.

Andesite?

This was originally one piece of stone?

And they moved this by hand? -Yeah.

That's the part of this I don't get.

Yes, it is. It is.

And they didn't just move this stone a few feet.

The andesite quarry is 55 miles away,

but how it got here

is just one of the many mysteries

surrounding the sun gate.

I've also heard some very outlandish stories about, like,

animals that are hidden here in the glyphs.

So, what do people see here?

An ancient elephant,

oh, with, like, the eye and the trunk here?

Yeah.

Prehistoric elephants disappeared from south america

more than 10,000 years ago, suggesting to some that tiwanaku

was the first major city in human history

and inspiring wild speculation

that it was built with ancient alien assistance.

But jose has a much less "stargate"-y theory.

So, this is not evidence of ice age encounters here?

Good. Okay. No, this is good.

We're getting the real story here.

I like this.

Gates: Modern archaeologists date the gate

and the rest of the city to about 1,500 years ago,

not 10,000.

That still doesn't explain how this place was built,

and jose says that new finds at the site

are only deepening the mystery.

Gates: One thing you can't tell in the dark

is how big this place is.

How big is it?

Two square miles? Yeah.

That's only the parts you've excavated?

Yeah. That's crazy.

And this huge mound that we see over here, is that natural?

All of it?

That's gigantic.

Gates: I'm in bolivia amidst the ancient ruins of tiwanaku,

a city of gigantic stones that were somehow moved here

nearly 2,000 years ago.

Legends say the city was built by an enigmatic god

who came from the nearby lake

or even ufos.

But I'm here for the truth,

and archaeologist jose ignacio gallegos

may be about to crack the code

on how this colossal city was really made.

And this huge mound that we see over here, is that natural?

All of it? Yep.

So, this is like a pyramid?

That's gigantic.

How much of this has been excavated?

3% of the pyramid has been excavated?

Crazy.

Gates: The akapana pyramid is a massive structure

that once stood five stories tall

and is wider than the great pyramid of giza in egypt.

Archaeologists believe that, at the city's height,

between 20,000 and 40,000 people lived or traveled here.

This culture may have controlled an empire

that extended from the coast of peru to bolivia

and northern chile.

And the heart of that empire was the capital city of tiwanaku,

home to some of the most mysterious

construction in the world.

And the most baffling of all is the pumapunku temple complex.

And this place just gets weirder and weirder.

Yeah.

What are these here?

They are. They're like giant h's.

Feels like lego set.

So all these little indentations that we see on the side,

all these little elements,

they're meant to link these things together?

Gates: Interlocking channels carved in the rocks,

mysterious shapes,

cryptic symbols,

and doorways within doorways.

The original function of these ruins has been lost to time,

but recent excavations may offer crucial clues.

Archaeologists have found thousands of ceramic vessels

for drinking chicha --

an alcoholic beverage made from corn,

as well as imagery depicting psychedelic rituals.

They've even uncovered implements

for snorting hallucinogenic compounds.

In short, this place may have been

the ancient equivalent of burning man,

a ceremonial center built to honor

the enigmatic deities of the sun and the nearby lake.

Wait. Is this one stone?

No...Way.

Gates: These blocks are the biggest in tiwanaku

and some of the largest in the ancient americas.

Each weighs as much as 100 cars, and consider this --

the tiwanaku didn't have the wheel,

yet the builders somehow moved every stone to the site

from someplace else.

This was not here? Nope.

No. Impossible. [ laughs ]

crazy.

Gates: All the stones at tiwanaku

were quarried from one of two places --

from deep in the mountains 10 miles away,

and from the other side of lake titicaca,

more than 55 miles away.

And in a sunken courtyard nearby,

you can even come face-to-face

with some of the ancient builders.

Wow, look at that!

Leaders and priests... Yeah, that's right.

...Kings.

That, by the way, is an alien.

That's not human. -No.

Even you think that doesn't look human.

It's either an ugly guy or an alien,

but I think, case closed,

this place was built by extraterrestrials.

That's it. You're right.

This place was built by aliens, for sure.

Gates: All joking aside, jose believes

the real answer to how tiwanaku was built

isn't up in the stars,

but rather lies hidden beneath our feet.

Revolutionary scans conducted by unesco

used 3-d imaging drones to build a topographical map.

This map revealed disturbances in the landscape

that jose is racing to investigate.

So, these are the things that we know about.

What did you find on the scan that we didn't know about?

35 acres of new finds?

Gates: To put this in perspective, the scan suggests

tiwanaku is about 10 times larger

than anyone previously believed.

Jose thinks these foundations buried underground

may be the key to understanding

how the massive stone structures of tiwanaku were built.

So, that's a totally buried structure?

Yeah.

No idea what that is?

And where is this in relation to where we're standing?

Gates: Jose has an imaging expert on standby

to investigate the buried ridges.

We make our way to the site where I find a familiar face.

Bob leonard.

Josh gates, how you doing, brother?

Gates: I last worked with him in guatemala

on my search for the tombs of the maya snake kings.

So, what's the plan out here, guys?

Well, we've been looking at jose's scans,

and they look like there's something really interesting here,

and so what we do now is go in and confirm it

with ground-penetrating radar.

All right. Let's rock and roll. Come on.

Gates: Gpr sends radio waves into the ground

and can detect the presence of structures

hidden more than a dozen feet down.

I drag the unit in a grid pattern

over the area indicated by the scans

while bob takes note of any disturbances in the data.

Bob, I just ran over some cow poop.

I'm sorry. Great.

Let's just call it a $15,000 piece of equipment

and try to keep it out of the [bleep] please.

Sorry. I'll do my best.

♪

can you hold it right there, josh?

That looks really interesting.

See how that blue got a lot fatter there?

Look at that.

Yeah. Yeah.

It almost looks like a depression.

Yeah, some kind of a pit.

That dirt looks disturbed.

Okay, great. Let's go back over this again,

see if we hit it on the other way.

All right.

Gates: We tag our first radar hit --

an unusual sunken area covered over with topsoil.

It appears to be man-made, so we continue scanning.

Whoa! That's getting some good hits.

Look at that. Look at that.

-Right there! -Yeah.

Yeah, that's crazy.

That's the biggest thing we've hit.

See how that bumps up?

-Yeah. -Bumps up.

It's a monster. Yeah.

So there's something right underneath us

that runs this whole length here?

Yeah.

Is it possible to dig it?

Okay. Yeah, let's dig.

Gates: Workers arrive on the scene within minutes

and start clearing away the thick brush

for a small test pit.

You know, bob, there are more shovels around here, I think.

I can get you one.

Well, but my hands are full over here.

I got, you know, expensive gear all over me.

Oh, I understand. I understand.

♪

the first foot or so yields nothing.

But soon, we feel resistance.

-Oh. -Hey.

I got something.

You have it down there? Yeah.

Oh, there's something here. Hold on.

Ha! Look at that!

That is stone!

Gates: I'm on a mission to find out

how the mind-boggling ancient city of tiwanaku was built.

Stone blocks weighing 100 tons were moved here from far away,

but how?

Now satellite scans and our own radar survey

have revealed something hidden underground

that might provide the answer.

Oh.

I got something.

You have it down there? Yeah.

Oh, there's something here. Hold on.

Stone? Yeah.

Ha! That's stone! Look at that!

That is stone!

This is a wall. Yeah.

It keeps going over. Hey.

I mean, this really is the edge of a wall.

Nice work, man. [ laughs ]

gates: This is a major find,

but curiously, one member of our team isn't celebrating.

The gpr hit was bigger than that,

so there's got to be more wall.

Okay, let's try and open this up this way a little bit.

Let's see what's down here.

So, clay, some sort of a surface here, clay.

We carefully scrape away more topsoil.

And...

Ah, more stone.

Look at that. Nice work, man.

Lo and behold, there's another structure

running parallel to the first.

This isn't just a small piece.

On the radar and on your scans,

this looks like it extends way out in both directions.

Okay, so, million-dollar question is, what is this?

What are we looking at?

Like canals?

And what about that sunken pit that we saw with the radar?

Could that be tied to all this?

That pit is some sort of water-collection system

like a reservoir?

There is evidence all over tiwanaku

of the importance of water,

like the mysterious staff god

who supposedly came from the waters of the lake

and the gutters and channels seen around the main temple

to collect and convey water around the site.

Okay. What'd you find?

Jose theorizes that the walls we just discovered

were part of a canal system

that brought controlled rivers of water into the city.

And satellite imagery confirms

that these canals connected natural waterways

near the stone quarry in the mountains down to the city.

Even if they have these canals coming down from the mountains,

how do they get the stones down the canals?

You float them?

[bleep]

[ laughs ] no.

How do you float them?

Reed boats? Like this?

Boats made out of this... -Yes.

...Float a 100-ton stone?

They still work with this?

It seems like an improbable solution

to the mystery of tiwanaku's construction.

Could boats made from blades of grass

really carry stones weighing hundreds of tons?

I'm skeptical, to say the least.

So, I bid jose and bob farewell and set my sights west

to the place where the uros people still live

and still carry on traditions that date back to the tiwanaku.

♪

outside of these cities in bolivia,

there's a whole lot of, well, not much,

but there is one site

that dominates this otherwise dusty landscape.

Lake titicaca.

[ record scratches ]

what are you, 12 years old?

That's the name of the lake.

Okay? That's its name --

lake titicaca.

Let's just... Back to the package, please.

[ clears throat ]

as I was saying, lake titicaca

is the largest lake in south america

and the highest navigable body of water on earth.

The route to puno, where the uros people live,

offers up some of its most spectacular vistas.

The lake is so big that it actually spans two countries,

so it's time to say goodbye to bolivia...

And hello to peru.

Gracias.

Across the sort of border,

I make my way to the western shore of lake titicaca

and the village of puno.

At the edge of the water, I meet an old friend,

an author specializing in ancient andean cultures,

brien foerster,

and an expert in the uros people,

local guide gustavo morales.

They've spent decades

investigating tiwanaku's legends.

Welcome to lake titicaca.

Beautiful place to be in the world.

I've just come from the ruins at tiwanaku.

How did they get these stones there?

The red-sandstone quarry is 10 miles away.

Yeah.

And the andesite quarry's 55 miles away.

Well, that's why I'm here because that's the part

that really I couldn't get my head around, you know?

In working with the archaeologist at the site,

he was saying that one of the theories

is they used this stuff, reeds,

and so he wanted me to come meet the uros people.

Now, who are the uros? Let's start with that.

Well, the uros is another ancient civilization

always around the lake titicaca.

And they were experts on building with reeds.

And so, what about this idea

that they could've constructed something out of reeds

to move tons and tons of stone?

Is it possible?

I think it is.

But in order to understand, you need to see it.

And we've arranged a boat

to take us all to the uros islands

to go and visit the uros people.

Okay, great. Where is it?

Out there. Wait, is this it?

It is. Yes, that's it.

[ laughs ]

is that made of reeds? It is.

Come on.

Gates: The boat approaching the docks is a marvel of ancient design.

Nearly everything,

even the puma heads on the front,

is made from natural reeds.

We climb aboard to test it out.

♪

this is the coolest boat I've ever seen.

I'm amazed by this thing.

I mean, these reeds right now are carrying the weight of...

One, two, three, four, five people.

Just the fact that we're standing up here

means that these reeds actually can support a lot of weight.

Nine tons?

Okay.

And actually, the size of the boat is unlimited.

All you do is add more and more reeds,

and you get bigger and bigger and bigger.

Right.

So, these things really could have carried huge stones.

Well, as you're about to see,

they can carry a lot more than that.

We take our plant-based transport further into the lake.

Soon, we see specks of land on the horizon.

Gustavo, what's this ahead of us?

Josh, welcome to the uros islands.

These are man-made? Yes, they are.

All made of reeds.

Oh, man!

Gates: I'm in the heart of south america's lake titicaca

investigating the theory

that the tiwanaku used boats made of reeds,

like the one I'm on right now,

to ferry stones to their capital.

It turns out that the uros people

still use this technology today and on a grand scale.

Gustavo, what's this ahead of us?

Josh, welcome to the uros islands.

These are man-made? Yes, they are.

All made of reeds.

Oh, man!

Before us is a sight

unlike anything I have ever witnessed --

a floating civilization built with ingenuity

and billions of blades of lake grass.

It's like another world.

We dock our floating salad,

and I step off onto what feels like terra firma -- sort of.

I cannot believe I'm walking on an island made of reeds.

Mm-hmm.

And it's not just the island.

There are houses, playgrounds, kitchens,

schools, and this thing -- all built from the same stuff.

In fact, there are 120 reed islands

floating together in lake titicaca,

and they're growing more of them every day.

The reed islands are capable of supporting fishing...

Like an ice-fishing hole... Exactly that.

...But a reed-fishing hole. Yes.

...Agriculture, and if the crops aren't plentiful,

the reeds turn out to be plenty tasty on their own.

It tastes like celery. It really does.

You could build with this stuff,

and you could make a killer bloody mary.

Give it a little stir.

Gates: But brien and gustavo didn't just bring me here to prove

that these reeds could've moved the stones at tiwanaku.

They've been investigating another mystery --

rumors of a lost tiwanakan city

sunken in the depths of lake titicaca.

Josh, she's cristina. She's the chief of this island.

Gates: To hear the folklore behind the so-called atlantis of the andes,

brian and gustavo sit me down with the island's chief,

cristina suaña coila.

There's so many stories

about the tiwanaku here in this lake.

What do your people know about them?

Translator: I remember that, many times,

my grandfather would tell us stories

about a tiwanakan city under lake titicaca.

He said that sometimes,

you could see the underwater city shine

because it was made out of gold.

Do you put any credence in these myths

that there's something under the lake?

I always listen to what indigenous people have to say

because they're the ones that know their history.

Right.

There are many stories about this lost city.

It's like atlantis. Right.

If the ruins are real,

why do you think they haven't been located?

There are new efforts to explore the lake,

and there are archaeologists working on this right now.

Right now, they are? Yes, they are.

There are many ancient sites around lake titicaca

that most peruvians don't know about.

One that we found recently has a large stone coiled serpent,

and the serpent's eyes are facing tiwanaku.

And the area is called wiñayamarca.

Wiñayamarca?

Wiñayamarca. And wiñayamarca means "eternal city."

that's its name? Yes.

That obviously is describing a place

likely made out of stone.

Right, something that lasts.

Exactly. Great.

Cristina, thank you very much.

Gracias. I appreciate it.

Thank you.

Gates: While brien and gustavo continue their research

with the uros people,

I catch a new ride to begin my new mission

to track down the ultimate tiwanaku legend --

the lost city of lake titicaca,

the fabled atlantis of the andes.

Now, this is what I'm talking about.

Look at this thing -- lap of luxury.

This thing even has armchair ashtrays.

You don't find that on a reed boat...

Because it would be a major fire hazard.

Right now, this high-tech hydrofoil

is carrying me from the uros floating islands

to a part of the lake called wiñayamarca, the eternal city.

Explorers have been searching different parts of the lake

for the fabled underwater city for decades.

In 1968, the great jacques cousteau himself

spent weeks searching for the ruins.

But he never searched the waters of wiñayamarca.

Now I'm meeting with underwater archaeologist

marcial medina huanca,

who has uncovered the best evidence yet

of this lost atlantis.

Marcial, hola. Mucho gusto.

Josh. Marcial.

Nice to meet you.

Pleasure. What is this?

[ speaking spanish ]

translator: These are remains of a lost tiwanaku temple.

It is? Yes.

It was a massive structure

with a coiled snake carved at its center,

perhaps representing a deity.

It's huge. [ speaking spanish ]

gates: Marcial uncovered these ruins only recently,

and they're virtually unknown to the outside world.

If they were built by the tiwanaku,

they would be among the only structures

found outside of their main capital.

And so do you think there were other tiwanaku buildings here?

Yes, I think this was a city that sank

as the levels of the lake changed.

Do you think there's more out there?

Sí. Can you prove it?

Sí, se por probar.

Yeah? Se por probar.

I'd like to see that.

Gates: Marcial is confident that the ruins lead out

to an underwater city.

To test his theory, we head to the nearby docks

to meet his sonar-scanning team,

krist geriene and rob veal from codiscovery,

a company specializing in underwater survey tech.

We ready to go?

We're all set. All the gear is set.

Okay.

Gates: We cast off and head to the area

directly offshore from the temple ruins.

There, we'll run a search grid,

working our way from the center of the lake

back toward the temple.

Es aquí.

-This is it? -Sí.

Okay, great. We're here.

You guys ready to scan?

Yeah. Okay.

Yeah, let's get into it. Come on.

[ engine starts ]

to see if the ruins onshore are just the tip of the iceberg,

we're going to deploy the team's

otherworldly looking secret weapon.

So, the nova ray was designed to be towed

or fly under its own power. Got it.

I've equipped this particular model today

with an exterior forward-scan sonar.

Awesome.

Under the wing on the skids, I have a side-scan sonar,

so we can look side to side

at the same time as we're looking forward.

This thing's got two sonar systems

and one, two, three, four cameras onboard?

That's correct.

And so are you helping to manage the tow?

Correct. I'll be on the back of the boat

managing the vehicle and the cable.

Got it. All right. Well, let's get into it, guys.

Come on. Let's do it.

Gates: We get the unit up and running...

-There we go. -She's in.

...And monitor the readings coming in

as the nova ray stitches the data together,

painting a detailed picture of the lake bed in real time.

Look at that. Unbelievable.

Marcial, what are we looking for down here?

[ speaking spanish ]

translator: We're looking for stonework underwater,

anything that can connect to the ruins we saw on land.

Gates: At first, all we see is an endless bed of reeds.

♪

and then we pick up something unusual, something big.

Right there, look at that.

Something just went right by the camera.

Yep, that had a nice straight line.

There's something there.

Excelente!

Gates: All along the edge

of lake titicaca in bolivia and peru

are ancient ruins whose origins and meanings

remain shrouded in mystery.

But about 50 miles from the border,

there's one site I've always wanted to visit.

So, this is incredible.

This is the so-called gate of the gods.

This gigantic stone carved doorway

that may date back to the inca or even to the tiwanaku.

No one knows for sure who made the carving or why,

but legend holds that an inca priest

fleeing spanish conquistadors

came here with a sacred artifact called the golden sun disc.

He inserted it into a circular notch in the carving

and was miraculously teleported to safety.

So, I don't happen to have a golden sun disc,

but according to the story, if you just step into the gate,

you'll actually disa--

guys! Guys, it works!

It totally works!

What? Whoo!

Gates: I'm in south america

investigating the legend of an ancient city

built by the mysterious tiwanaku civilization

that may be lost in the depths of lake titicaca.

We've used sonar to scan the lake bed for ruins

and just got a significant hit.

Right there, look at that.

Something just went right by the camera.

Yep, that had a nice straight line.

There's something there.

Excelente!

That could be a stone.

And those stones would be made out of what material?

[ speaking spanish ] [ speaking spanish ]

andesite.

Andesite -- the exact type of stone we saw at tiwanaku.

This could be a major breakthrough.

Marcial and I quickly gear up to investigate.

High-altitude diving, though, is no joke.

Because we're at 12,500 feet,

the pressure underwater is three times more intense,

which means less time at the bottom.

♪

♪

beneath the boat, the water is clear,

but that doesn't mean it's easy to see.

We carefully enter an eerie forest of reeds.

♪

♪

we continue searching for cut stone,

but it's like looking for a needle in a reed stack,

and every time we touch the bottom,

huge clouds of silt rise up to plunge us into twilight.

The clock is ticking.

We have just 20 minutes left

before we'll be forced to ascend.

Luckily, the thick vegetation clears,

revealing something truly incredible.

The wall stretches out as far as the eye can see.

We follow it and reach a far larger structure,

ruins of something big, perhaps even the remains of a city.

♪

we're both stunned by the discovery

and deeply out of breath from the altitude.

Marcial and I make a few more laps around the ruins

and then return to the surface.

Whoo!

Wow!

Unbelievable.

It's this huge structure. -Mucho.

Yeah, there's so much stuff,

and you can see all the cut stones.

[ speaking spanish ]

translator: We found wall after wall.

It's crazy.

You think this could be part of a city?

Sí.

And what percentage of this lake have you searched?

Translator: 0.001%

that's it?

[ laughs ] nothing.

A lot of work left to be done.

Hey, great job.

Oh, that was awesome.

Whoo! Loco.

Crazy. Loco is right.

That's loco.

Gates: Marcial and his colleagues will return to the site

with more resources to see if the atlantis of the andes

is as extensive as legends claim.

The tiwanaku worshipped an enigmatic god

who came from the lake,

which seems fitting since these waters appear

to have both created and destroyed their accomplishments.

Discoveries suggest their capital

was a place of mind-altering rituals

brought to life by canals

used to float masterful monuments into place.

♪

and now, it seems another of their cities

may have been drowned beneath the waves.

But thanks to the determined archaeologists and explorers

investigating the tiwanakus' history,

the true extent of their achievements...

Is finally being revealed.

♪