Original subtitles

NARRATOR: High in the Andes Mountains,

more than 150 massive stone blocks

lie scattered on the ground.

GIORGIO A. TSOUKALOS: Puma Punku is one of the most enigmatic places

on planet Earth.

Some of the stone blocks are over a hundred tons.

NARRATOR: The ancient blocks are carved with incredible precision.

TRAVIS TAYLOR: It's an amazing piece of engineering

that is beyond its time.

NARRATOR: But the origins and purpose of Puma Punku

remain completely unknown.

Mainstream archaeology says that this site is

1,500 years old,

but anyone you talk to in that community

will tell you it's much, much older.

NARRATOR: Could new advancements in technology

finally help to solve a centuries-old puzzle

and offer proof of alien intervention on Earth?

ERICH VON DÄNIKEN: The locals say, "It was not us who made these platforms.

"It was the gods.

The gods who descended from the sky."

NARRATOR: There is a doorway

in the universe.

Beyond it is the promise of truth.

It demands we question everything

we have ever been taught.

The evidence is all around us.

The future is right before our eyes.

We are not alone.

We have never been alone.

High in the Andes Mountains,

Spanish explorer Pedro Cieza de León is

searching for the Inca capital of Qullasuyu.

Just south of Lake Titicaca,

at an elevation of nearly 13,000 feet,

he comes upon extraordinary ruins

covering roughly two and a half square miles.

It is the ancient settlement of Tiahuanaco.

De León spends many months investigating the site

and writes in his chronicles

that Tiahuanaco contains impressive stone walls,

idols of human figures, and great doorways.

He also writes about an area

south of the main archaeological site

called Puma Punku, or "Gate of the Puma."

It features stone blocks so enormous,

he does not understand how they could be moved by humans.

And they are carved with a precision

that, according to De León, could not be accomplished

with the tools available to the Inca.

TSOUKALOS: Pedro Cieza de León says

that the local population,

which was Inca, told him...

...that this place was not built by the Incas

but it was built hundreds of years before.

If the Inca themselves have said that it was not the Inca,

well, then, who were the pre-Incas?

And there we are confronted with a gigantic question mark.

NARRATOR: What the giant blocks formed is completely unknown,

and nearly five centuries after its discovery by De León,

Puma Punku remains as mysterious as ever.

It's out in this really open high plains.

Most of the stones in Puma Punku are huge.

The biggest is 130 tons.

There's another one that's 85 tons.

Even the small ones are multiton.

So these are huge.

The Plataforma Lítica is in the center of Puma Punku

and it's, in fact, the foundation.

So it consists of enormous slabs of red sandstone

that were brought from a quarry eight miles to the west,

over two mountain ranges.

So, how that was accomplished, I have no idea.

CAROLINE WHITEHILL: Another really fascinating

aspect of the Puma Punku site

is the distribution of these blocks.

Some of them are still upright in the position

that they were originally constructed in.

Most of them are strewn about.

It looks like you're in a child's playroom

and blocks have just been knocked over

from some sort of a structure that was built.

HUGH NEWMAN: It looks like it's been destroyed

by a kind of tsunami or something.

It's got mud piled up everywhere.

Giant stones sticking out of it at crazy angles.

NARRATOR: It remains unknown

whether the structures of Puma Punku were destroyed

by a cataclysm or if the construction project

was simply abandoned before it was finished.

But the roughly 150 megalithic blocks

that can be found at the site today

reveal that the builders possessed

astounding stoneworking abilities.

BARNHART: Puma Punku has these megalithic blocks

that are perfectly cut...

...that all of their angles are completely right angles.

There's these ones in particular called H-blocks

that look like a big capital "H."

They have kind of, uh, fade lines going in

where they carved the same shape in a couple of different layers,

deeper and deeper into the stone.

And its precision is really mind-boggling.

TAYLOR: There are grooves that are cut with perfect 90-degree angles.

It looks like they were so precise

that they were done

with modern-day milling machine tools.

DAVID CHILDRESS: There's stones there, too,

that have a lot of drill holes

and saw cuts and things like that in them.

It's an amazing piece of engineering

that is beyond its time.

TSOUKALOS: Predominantly, we have two types of stone at Puma Punku,

and that is red sandstone and gray andesite.

They have found tools made of copper

and of iron and bronze at Puma Punku.

And with those tools, you can absolutely cut the sandstone.

However, you cannot cut the gray andesite blocks

with bronze or with copper or with iron.

What's interesting, too, is that the stone blocks

that we find at Puma Punku,

the surface is as if you're touching glass.

It is perfection.

So, to me it's possible that our ancestors figured out

a way to vitrify stone.

And we have evidence here of some type of a heat tool.

NARRATOR: In 1903, Arthur Posnansky,

an Austrian engineer, explorer, and amateur archaeologist,

traveled to Puma Punku,

which by that time was located in Western Bolivia.

Posnansky began the most thorough study

of the site ever conducted.

Arthur Posnansky was born in Vienna, Austria

in the 19th century,

and in his early 20s he moved to South America.

But very soon after that,

he became fascinated by Puma Punku

and spent almost the rest of his life

studying and researching that location.

TSOUKALOS: Arthur Posnansky lived and researched at Puma Punku

from 1904 until 1945.

He was there for 41 years

and he absolutely fell in love

not only with the landscapes there

but also with that culture that put a spell on him,

and it was his biggest siren call.

When speaking with the Aymara elders,

they speak very, very fondly

of the archaeologist Posnansky...

...because he respected them and he respected their culture.

And he talked to them about what they knew about these sites.

And one of the places that they're in agreement

is that the site is much older

than it's believed to be by mainstream archaeologists.

NARRATOR: Mainstream scholars believe

the site was originally constructed

about 1,500 years ago, but Posnansky proposed

that Puma Punku was much, much older.

By examining the structures and what he believed was

their original alignment with the stars,

he dated the ruins to 15,000 BC.

TAYLOR: Arthur Posnansky suggests that Puma Punku would line up

with stellar objects about 17,000 years ago.

The local Indigenous people, the Aymara, uh, they actually

have a mythology that Puma Punku has been around

for maybe as much as 17,000 years.

NARRATOR: The Aymara people have occupied the area

of modern-day Peru and Bolivia for at least 800 years

and lived alongside the Inca when Pedro Cieza de León

arrived at Tiahuanaco in the 16th century.

Both the Inca and Aymara told De León

and other Spanish chroniclers

not only that Puma Punku was built long before their time

but also that it was the work of the gods.

VON DÄNIKEN: The locals said,

"It was not us who made this.

It was the gods who did it in one night."

"The gods who descended from the sky."

So, normally every culture says,

"Oh, yes, we did it. We, we had the knowledge.

We were strong enough."

In that case, Puma Punku, the locals say,

"It was not us who made these platforms.

It was the gods."

Which gods? Extraterrestrials.

NARRATOR: The mystery of Puma Punku has persisted for centuries.

But now, thanks to new archaeological research

and cutting-edge technology,

experts believe they may finally be able

to accurately reconstruct the ancient megalithic site

and, in the process,

perhaps answer some of the long-standing questions

about Puma Punku's age, how it was built,

and its potential extraterrestrial origins.

♪ ♪

NARRATOR: Western Bolivia, 1995.

Archaeologist Alexei Vranich is preparing to excavate

an ancient structure at the site of Tiahuanaco

for his PhD thesis.

When the project runs into complications,

a local archaeological team

invites him to instead visit the ruins of Puma Punku.

VRANICH: The Puma Punku is located at Tiahuanaco

just a little bit south of the village.

It's one of the more dramatic landscapes you can find

at 13,000 feet above sea level.

And you simply don't expect to find something so impressive

in such a desolate landscape.

I remember seeing it, and I had no idea what I was looking at.

It was a confusing mess,

and I had never seen anything like it.

NARRATOR: Upon seeing Puma Punku,

Vranich decided to make the site

the new focus of his excavation project.

VRANICH: I lived in the village with the Aymara Indians,

and these are local people that have been there for centuries,

and they worked directly with me,

so I got to know the culture very well.

They're excellent excavators.

But they also held it in high esteem

within their cosmological world.

WHITEHILL: When you speak to the elders of the Aymara,

they will tell you that this was actually built by the gods,

that these were gods that came down.

NARRATOR: Jorge Delgado,

an Inca by birth and heritage,

says that in the Native tradition,

the gods connected with Puma Punku

are known as the Space Brothers.

...ways how we can become one with the stones.

NARRATOR: The first known photograph of Puma Punku was taken in 1893,

and the site has transformed dramatically since that time.

In fact, the entire area of Tiahuanaco

is like a giant puzzle with many pieces missing or moved.

TSOUKALOS: Half of Tiahuanaco town

was built with Puma Punku stone

and with Tiahuanaco stone from the ancient sites.

I mean, there is one block at a gas station.

The cathedral, or the Church of Tiahuanaco--

a third of it is Puma Punku Tiahuanaco rock.

It puts a giant damper on trying to figure out

what did Puma Punku look like in its heyday?

NARRATOR: Even the Bolivian government

has been responsible for altering the landscape.

VRANICH: In the 1950s,

the Bolivian government decided that they wanted

to have ruins

similar to what Peru had for Machu Picchu

or Mexico had for Teotihuácan.

So, it was a very progressive agenda

to give the Bolivian people a pre-Columbian identity.

But the result for archaeology was a bit of a disaster.

They moved around a lot of stone

and did a lot of questionable reconstructions.

NARRATOR: While performing excavations at the ancient site,

Dr. Vranich decided to embark on his own reconstruction project

in hopes of answering some of Puma Punku's many mysteries.

Dr. Vranich's reconstruction would be computer-generated,

and the first step was to precisely measure

every stone block.

VRANICH: I used a lot of interesting and new technologies

from laser scanners to photogrammetry.

But the best method ended up being tape measure,

pen and paper.

And I used the notes from scholars

from over a century ago, from the 1840s to the 1890s.

And then, recently, an architect from UC Berkeley

did a lot of the drawings of these stones,

and that became the basis for the reconstruction.

NARRATOR: Once Dr. Vranich completed the arduous task

of documenting the measurements of every known stone block

and slab at Puma Punku,

he 3D-printed them at UCLA,

where he was working as a research associate

and visiting assistant professor.

With help from his students,

he began putting together the puzzle pieces.

We had a lot of pieces,

and we had no idea how to go about putting it together.

There was a couple of rules that have been found

on how some of these stones,

or how some of the ornaments, fit.

Certain types of windows or niches are always found

in certain patterns or in certain combinations.

We continued to play with this model

probably for over a year.

And we were almost at our wits end going,

"We're not gonna be able to put this together,"

when we finally had a moment of insight.

We were able to put together

two different pieces that formed

what one wall of the temple would have looked like.

NARRATOR: Dr. Vranich and his students had discovered

what he calls the Tiahuanaco Rosetta Stone.

VRANICH: That allowed us to find the other pieces

and fit them together.

And once we had that, we realized we actually had

a miniature version of the Puma Punku

down to almost exact size, 0.57 in scale.

That was one of those

aha moments that almost surprises you.

For an archaeologist, it's one of those moments

that you live for.

NARRATOR: Once Dr. Vranich and his students

established how the pieces fit together,

they were able to do a complete reconstruction of Puma Punku.

VRANICH: Puma Punku-- it's two different things, in a way.

One of them is the entire temple complex,

which is almost half a kilometer long.

There's the main platform, there's a plaza in front of it,

there's a couple of different walls.

So, it's a substantial building.

But surrounding the inner courtyard,

you would have had these buildings

that we're reconstructing right now.

So, we're reconstructing

the main religious and ritual focus

of this larger temple complex.

The Puma Punku probably had formed

part of the religious ideology that Tiahuanaco

was an important place on Earth where all the forces

of the heavens and the underworld

were mediated to create

a fertile and safe Earth.

NARRATOR: Dr. Vranich has assembled the most complete model

of Puma Punku ever constructed.

But just how accurate is it?

And could it provide the key to solving

the centuries-old mystery of Puma Punku?

NARRATOR: Over the past 20 years,

archaeologist Dr. Alexei Vranich

has taken detailed measurements

of every existing megalithic block at Puma Punku

and had them 3D-printed.

By working with his model, he has developed a theory

on how the ancient site was originally constructed.

On March 5, 2024,

he invited Giorgio Tsoukalos

and aerospace engineer Dr. Travis Taylor

to a workspace in Los Angeles

to share the results of his research.

Tell me what this template is that's on the tabletop here.

VRANICH: This represents the sandstone foundation

for this building of the Puma Punku.

And to print it out was simply too cumbersome,

so we put it out on paper.

Put that in scale for me. How-how far

-is this piece of paper? -So, this one's about

-maybe 70 meters long by about 12 meters wide. -Oh, okay. Okay.

-And... -And consisting of how many platform?

So, we have 17 different pieces

of sandstone that would have completed a very flat surface.

And there's an excellent chance it probably would have extended

another 12 meters this way.

TSOUKALOS: When I saw the model in person,

I was like, "I cannot believe my eyes."

It almost looked like a very long

and rectangular building

with multiple structures lining up a long avenue.

Alexei, clearly, this is a passion for you.

My-my question is, if I were to compare

all the cuts and everything to the actual one,

how closely would they compare?

-No, they wouldn't. -Really?

VRANICH: I wanted to know what these blocks looked like

when they were made, not how they were damaged

or worn over the years.

I needed to know, "How were these things meant to fit?"

So, you-you would suggest, then,

that these blocks

are what they actually looked like when they were made.

VRANICH: Exactly.

Well, that's amazing. I mean, the first time I was there,

uh, was in 1995,

and in 1995,

one of the most fascinating blocks I've seen

is this guy right here.

VRANICH: This stone...

-This is what you were looking at, correct? -Yes. Mm-hmm.

So, it's a stone-- it's a window within a window

-within a window. -TAYLOR: Yes.

TSOUKALOS: Wow.

TAYLOR: You have to have done

ground-penetrating radar,

uh, and other sensor measurements out there.

Is there more to it underneath the surface

that we're not seeing here?

We actually did one of the most extensive

ground-penetrating radar surveys for the entire continent.

And then UNESCO went by and did a drone survey,

uh, and it picked up every tiny bump across the surface.

And, yeah, they definitely showed

that the Puma Punku is quite large

and there's a lot more of these stones.

Do you have any conclusion what any of this means?

This is a temple, it's a ceremonial place.

That-That's clearly evident.

TAYLOR: Alexei, looking at all the parts here, uh,

I could probably come up with a billion combinations.

So, how certain are you

that this is the right combination?

Or that there's iterations of it, versions of it,

or something completely different

that this could've possibly been?

You know what, I-I'm fairly confident

about the general form

and the location of certain things,

that's for sure.

NARRATOR: While working with his 3D printed model,

Dr. Vranich made an extraordinary discovery

about the purpose of the intricately carved blocks

at Puma Punku.

Come over here.

We just printed this one out.

If this is the way it should have gone,

with here, and then it would have had a little bit on top.

From this point, it doesn't seem like much.

But come around this side.

Now look through the door

and what do you see?

-Bring yourself down. -So like this?

Oh! Yeah!

And you know when you'll have the two mirrors

parallel to each other and you look

and it's like an infinity mirror, as they call it.

-VRANICH: Yes. -TAYLOR: It's kind of that effect.

Like you're looking to infinity.

It's forced perception.

It's a door within a door within a door within a door.

TAYLOR: What direction is this facing?

VRANICH: So this is facing, uh, west.

TAYLOR: Oh, so it would see a sunset?

VRANICH: Yes, yes.

TAYLOR: It would be very interesting to note

what time of year does the sun actually set perfectly

such that it illuminates the very center

of that infinity door?

It won't line up exactly right now,

but you could project that backwards in time,

and it would tell us when the sun lined up on that spot.

You could use this to date this room.

VRANICH: Right.

NARRATOR: Determined to solve the mystery of Puma Punku,

Dr. Vranich has released his 3D printing diagrams to the public

and has challenged other researchers

to reconstruct the ancient site as well.

There's a lot of pieces

that I haven't been able to place,

so that's why I placed all of this information online

along with the basic instructions.

I would love for people to download this, print them out.

My model is good for the moment,

but it's the basic model.

We can add a lot of things to it.

TAYLOR: What Alexei has done is absolutely fantastic.

Now anyone can take all the pieces there

and see if they can put them together in a way

that makes sense to them.

And sooner or later, someone is going to figure out

what all these pieces built, what they were,

why were they there.

NARRATOR: Now that accurate measurements of Puma Punku

are available online,

could this mark the beginning of a new era of discovery?

Perhaps further clues can be found

by examining another model of Puma Punku

that reveals that the site bears striking similarities

to some of the most ancient constructions on Earth.

NARRATOR: 3D data visualization expert Scott McAvoy

runs the university library's digital media lab.

He is also known for his CGI reconstructions

of ISIS-destroyed sites

in the ancient Syrian city of Palmyra.

Archaeological reconstruction is a way to put

a lot of different data together

in a way that we can draw connections

between ourselves and the way things were in the past.

If a picture is worth a thousand words,

a 3D model must be worth a million.

Puma Punku is a perfect target for this work.

It's dripping with mystery and it's very enticing.

NARRATOR: Now he has applied the data collected by Dr. Alexei Vranich

to create a digital 3D wireframe of Puma Punku.

-Hey, Scott. -Hey. Good to see you again.

Good to see you.

NARRATOR: On March 28, 2024,

Scott invited archaeologist Dr. Ed Barnhart,

who has conducted his own on-the-ground investigations

of Puma Punku to review his model

and discuss his findings.

BARNHART: I've been to Puma Punku three different times.

I have wandered this thing

and looking at it from different angles,

feeling stupid that I can't figure out

how any of these things go together.

McAVOY: Well, that's where technology can really help us.

-Let me show you what we got. -Okay.

McAVOY: So, this is the positions of the stones from 1893.

The stones had been moved so many times in recent years

and even in the past before this photo was taken.

We're trying to get a better sense

of where they might have laid.

This is a puzzle with probably 40% of its pieces missing.

McAVOY: I think it was calculated,

like, ten percent of the pieces are maybe here.

-Oh, my gosh, really? -Yeah. We're missing a lot.

This is only 150 bricks.

You know, if we put these up by volume,

I think it's going to make up, like,

half of the front facade.

-Oh, my gosh. -Yeah.

Here we're starting with the satellite image of Puma Punku.

And then we overlay, um, Alexei's map.

So here we have a basic 3D model

of the platform around it,

the plaza on the outside.

And we see that this temple is at the entrance

to this sunken courtyard.

That is fascinating.

McAVOY: From the incisions on the foundation here,

I feel pretty comfortable extruding the walls.

You know, raising these up to the height

of the doorway and trying to fill in that space.

Okay. That does make sense.

So, there seems to be an implied symmetry here.

There seems to be a pattern.

This side reflects this side.

So we're moving forward based on that.

BARNHART: Wow.

That makes logical sense to me

because the other parts of Tiahuanaco we can see

all adhere to a basic symmetry.

McAVOY: Well, you know, there's so many more pieces here that

I wasn't even able to find a place for,

especially these tub stones here.

BARNHART: You know, one of the real clues

is these little guys right here,

these, where we believe

metal, kind of I-bars, would keep them clasped.

There's another one there.

Those are exactly the kind of pieces

that I'm focused on to say like, "Okay,

this puzzle piece has to fit with this one."

Yeah, these are great.

NARRATOR: The type of connection

Dr. Barnhart is referring to

is commonly called a keystone cut.

On the blocks at Puma Punku are what we call keystone cuts.

And these keystone cuts are notches, like a T-notch,

set on the edge of a block that match a T-notch

on another edge of a block.

And then molten metal was poured

into those notches as a fastener.

NEWMAN: These keystone cuts are fascinating

because they're found not just at Puma Punku

and Tiahuanaco in Bolivia.

They're found in Peru.

They're found in Egypt. They're found in Greece.

And they even found at Angkor Wat in Cambodia.

So, does this prove that there was, like,

a worldwide technological civilization

that shared this knowledge?

TSOUKALOS: From the ancient astronaut perspective,

our ancestors all went to the same masonry school.

Meaning, the same extraterrestrial teachers

visited at Puma Punku

and the same teachers visited at Angkor Wat.

NARRATOR: Is it possible that Puma Punku

was visited by otherworldly beings

in the distant past?

Ancient astronaut theorists say yes,

and suggest Puma Punku presents evidence

that could push back the entire timeline

of human civilization.

NARRATOR: Muncie, Indiana.

April 9th, 2024.

At Ball State University, Giorgio Tsoukalos

is meeting with Professor of Electronic Art John Fillwalk,

who used the data gathered by Dr. Alexei Vranich

to develop his own model of Puma Punku.

So, here's what we've been working on.

Oh, wow. This is great. Look at all this.

This was probably the most challenging

reconstruction we've ever done.

So, how then did you come up with that particular structure?

The first thing, really, we tried to do

was reconstruct the foundation because that really informed

sort of the growth of the building out of that.

And a lot of the blocks are very specific to certain spots.

TSOUKALOS: Oh, wow.

FILLWALK: Then we create a motif

that expands around the structures.

You know, to me, it seems very mystical.

The patterning of the doorways within doorways within doorways

I mean, it really suggests an idea of a transition.

It points, to me, toward another reality,

maybe the afterlife, to honor ancestors.

NARRATOR: John Fillwalk's reconstruction,

much like the model built by Dr. Alexei Vranich,

contains doorways within doorways,

which he believes points to the site

having served a ceremonial function.

But the question remains: for who?

In 1945, after studying Puma Punku

for more than four decades, archaeologist Arthur Posnansky

published his findings in a book titled

Tihuanacu: The Cradle of American Man.

And in it, he proposed that the structures found

throughout the Tiahuanaco site-- including Puma Punku--

were built roughly 17,000 years ago.

The reason why he did that is because

of astronomical facts

that he found at Tiahuanaco.

These astronomical markers only

line up properly

around 15,000 BC.

CHILDRESS: Modern archaeologists have been

getting dates that are more like 500 AD.

But the dating is difficult.

Even today, archaeologists are not

in agreement of the dates of Tiahuanaco and Puma Punku.

NARRATOR: Posnansky based his dating

on features at a site located

less than one mile northeast of Puma Punku

called Kalasasaya.

John Fillwalk digitally recreated this ancient site

with its central sunken courtyard

and many monoliths

in order to look for celestial alignments

that might corroborate Posnansky's dating.

We're looking at Kalasasaya.

And Kalasasaya does have a beautiful equinox alignment.

You'll see the sun just sits there

-right on top of the, the stone. -TSOUKALOS: Okay.

FILLWALK: That's gorgeous.

TSOUKALOS: Oh, how cool is that?

So, we worked with NASA's

JPL Horizons group

to provide data on any kind of visible celestial body

-looking at 15,000 BC. -And what did you find?

So, there were some interesting alignments, I have to say.

At Kalasasaya.

Because there's all the verticals that point around.

And so we investigated that

from the center monument looking outward towards

those posts as almost like in Stonehenge

-where you look and you can see, -Right.

you know, solstice or equinox and that kind of thing.

That would essentially indicate

that Posnansky's calculations

in this particular case

were correct.

I mean, I think that's possible.

There are alignments.

-Wow. Okay. -Yeah.

-There are. -That date back 15,000 BC. I mean,

you know, all of this would essentially rewrite

South American history, and this is something to be

-excited about. -Yeah.

NARRATOR: If the Kalasasaya structure at Tiahuanaco

can be dated to 15,000 BC,

is it possible that Puma Punku is that old as well?

FOERSTER: There's no logic as to why modern archaeologists

put one fence around Puma Punku

and another around Tiahuanaco.

They're both the same location.

It's clear they were both built at the same time

by the same builders in the very, very distant past.

NARRATOR: Some researchers also believe

that the remote location of Puma Punku

would make more sense if it had been built 17,000 years ago,

because at that time, it may have overlooked

Lake Titicaca.

If you look at the geomorphology, if you look

at the sediments that have been deposited around the site,

you can see that the lake was at one point much, much larger.

COLLINS: Lake Titicaca today

is many miles away from Puma Punku,

but in the past it is believed that this was actually

much closer to Puma Punku.

-So, we're looking at Lake Titicaca right now, -Correct.

so where is, in this image,

where is Puma Punku located?

Yeah, so, right, so at the tail end

of the lake, here on the south,

kind of east corner, if you come out here into the plains,

it's a little bit offset into that area, that flat area.

Okay, and the idea is that long ago,

Lake Titicaca was much, much larger,

and so that Puma Punku and Tiahuanaco

may have been a harbor or a port

to Lake Titicaca.

Certainly would make sense, and water

is such a dominant feature at the site, as you know,

-with the canal structures -Right.

-and drainage systems and all of that. -Mm-hmm.

So, that connection to water, obviously, is really important.

NARRATOR: According to some experts,

Puma Punku's proximity to Lake Titicaca

in the distant past might also explain

why the site appears to have experienced a cataclysmic event.

FOERSTER: I think what was responsible was a massive

explosion of the volcano of Cerro Khapía

between 12,800

and 11,600 years ago.

Right next to that volcano

is the deepest part of the lake,

which is 800 to 900 feet deep.

So I think the debris that came from the volcano

created a tsunami that lifted up the soil

and sediment at the bottom of the shallow part of the lake

and literally buried Puma Punku and parts of Tiahuanaco.

TSOUKALOS: There is a possibility

that Dr. Posnansky's calculations are correct.

And Puma Punku may date back

as far as 15,000 years BC.

And if that is the case,

that is one of those times

where, in many cultures around the world,

including the ancient Egyptians,

are referring to a golden age

when the so-called gods mingled amongst humankind.

So, was this an early memory of first contact?

NARRATOR: Could it be that Puma Punku was built

more than 17,000 years ago

and has a connection to otherworldly visitors?

Perhaps further clues can be found

by examining a gigantic stone gateway

that might be the final piece of the puzzle.

NARRATOR: When investigating the ruins of Puma Punku

for insights about its mysterious origins,

ancient astronaut theorists believe

some of the most compelling clues

can be found by examining a giant stone doorway

that stands less than a mile away

in central Tiahuanaco.

Called the Gate of the Sun,

it is ten feet tall, 13 feet wide

and was carved from a single piece of andesite stone

that weighs more than ten tons.

Perhaps one of the most iconic works of Tiahuanaco

is the Gate of the Sun.

It was found nearby and ultimately moved

to its present location.

And they think that it could well have been,

actually, the entrance or gateway to Puma Punku.

It features the Inca god Viracocha,

who's the god of creation, who's portrayed

as a sort of a humanoid figure

with rays coming off his head.

NEWMAN: Interestingly, the god Viracocha

is holding two staffs.

And this is the most ancient version of Viracocha.

And so to find that there is really quite astonishing.

It's said that Viracocha himself,

the great god of the Andes, was actually the person

who instigated the construction of Tiahuanaco and Puma Punku.

So what's particularly fascinating about

the Gate of the Sun is that

on either side of Viracocha

are these figures on each side,

and they are birdmen.

TSOUKALOS: Viracocha is flanked

with 48 winged beings.

Now, why would these beings

have wings attached to them?

Well, because our ancestors

try to signify flight.

What I think is depicted

on the Gate of the Sun is a type

of a celestial pantheon,

suggesting that whoever came

and imparted knowledge

at Tiahuanaco and Puma Punku

were beings that had a celestial connection,

meaning they came from the sky.

NARRATOR: Could it be that the figures carved

on the Gate of the Sun are depictions of extraterrestrials

who arrived in Puma Punku in the distant past?

If Puma Punku was some sort of temple complex--

as Alexei Vranich, Scott McAvoy

and John Fillwalk have all envisioned--

was it built to connect with these beings?

For now, there remain more questions than answers.

But many researchers believe that solving the mystery

of Puma Punku could lead to even more profound revelations.

VRANICH: Puma Punku will be a mystery

for a lot of people for a long time.

And there are a lot of aspects and facets

of that society we don't know about.

Archaeologists will be able to work there for many generations.

We can continue to excavate,

uh, and do more advanced analysis

to try to find out a little bit more

about Puma Punku and Tiahuanaco society.

FOERSTER: Puma Punku is unique in terms of its construction,

its astonishing level of accuracy.

Flat surfaces almost laser flat.

So it makes it one of the most enigmatic

and fascinating ancient locations on the planet.

The level of technology required to create

Puma Punku would defy 21st century technologies.

So, how that was accomplished, I have no idea.

TSOUKALOS: Even to this day, with all the recreations,

nobody really has figured out yet

what that place looked like when it was finished.

What was Puma Punku made for?

Your guess is as good as mine.

But we may have a eureka moment

where, together,

we will unlock the great mystery

of Puma Punku.

NARRATOR: Since Spanish explorers first came upon

Puma Punku nearly five centuries ago,

the ruins have remained one of the ancient world's

greatest mysteries.

Like the pyramids that stand on Egypt's Giza Plateau,

the enormous Moai statues of Easter Island,

and the monoliths of Stonehenge,

might Puma Punku point to a history

that is much different than we've imagined?

Perhaps modern technology

will soon reveal Puma Punku's

long held secrets and the truth

about our alien ancestors.

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