Original subtitles

[William Shatner] An ancient desert

covered in hundreds of pyramids.

A massive earthen hill

hiding a sacred and deadly spring.

And a controversial discovery

hidden deep beneath the Alaskan wilderness.

For thousands of years,

civilizations around the world

built monumental structures made of stone and brick

that we call pyramids.

In Africa, Asia, Europe, and the Americas,

ancient engineers created

surprisingly similar constructions

while having no knowledge

of what other cultures were crafting.

How is this possible?

Were pyramids meant to be tombs or temples?

Or was there a greater purpose

to some of these incredible works?

Well, that is what we'll try and find out.

♪ ♪

[Shatner reads on-screen text]

Towering over the limestone desert sands

of the Giza Plateau stands the oldest

of the Seven Wonders of the Ancient World.

It is called the Great Pyramid of Giza.

Built in 2600 BC,

the monolith is flanked by two smaller

but equally colossal pyramid structures.

The Giza complex is a monumental achievement

in ancient engineering

and a marvel that has confounded

scientists and researchers for centuries.

[Hugh Newman] The Great Pyramid

on the Giza Plateau

is an astonishing construction.

There's 2.3 million blocks of limestone

in the structure itself.

I mean, it takes an hour to walk around it, at least.

But it's also the fact that you have these giant platforms

of megalithic blocks,

perfectly created.

[Chris Naunton] Inevitably,

people want to ask how on earth

a civilization thousands of years ago

could have achieved this.

The right angles at the corner

are almost absolutely bang on 90-degree angles.

The lengths of the sides are almost perfectly equal

on all four of them.

They are closer to perfect

than would be required for modern buildings.

It is a-an unparalleled achievement.

[Shatner] It's possible we'll never completely understand

how the great pyramids were constructed

with such remarkable precision.

But perhaps an even greater mystery

is why were they built in the first place.

The great pyramids of Giza are

one of the great untold mysteries.

We're not quite sure how they were used.

But what we see today

in the pyramids of Giza

are the-- sort of the bones of these buildings

in Egyptian antiquity.

The pyramids at Giza

were, uh, encased in white limestone

and presumably polished.

And so, during the daytime,

you would have seen these sort of white mirror-like surfaces.

What we're missing is the limestone covering

and the golden top piece.

But the pyramids themselves

don't have any particular explanation

of why they were built or the symbolic purposes of it.

So part of the mystery is trying to figure out

what is this thing.

[Robert Schoch] Ultimately, there are more questions

than answers when it comes to the pyramids

on the Giza Plateau.

Some of them were used as tombs.

But my own opinion is that that was

a secondary function for many of them.

[Shatner] If the great pyramids weren't strictly used as tombs,

as most mainstream Egyptologists maintain,

then what was their fundamental purpose?

[Shatner reads on-screen text]

This massive building houses the largest collection

of ancient Egyptian antiquities in the world.

Among the many treasures is a 3,800-year-old capstone

from the pyramid of King Amenemhat III

that some believe is connected to a mythical Egyptian object

known as the Benben stone.

[Schoch] In the Cairo Museum,

there is a pyramidion which is made out

of beautiful black basaltic type of rock from a pyramid

that seems to be our best representation

of what the Benben stone was like,

according to the ancient Egyptians.

That Benben stone goes back to maybe 1850 or so BC.

So it's not the original one,

but it represents what the original one was.

In ancient dynastic Egypt,

there was a literal Benben stone.

That Benben stone has long been lost, unfortunately.

But some people have suggested maybe it was a meteorite

that was pyramidally shaped.

And by the ancient Egyptians,

it had sacred power.

[Shatner] While some believe the original Benben stone

was a meteorite,

legends from ancient Egypt suggest

it was a place of divine creation.

Egyptian mythology says

that there were once

just waters of chaos.

[thunder rumbling]

And then what broke through

the waters of chaos was an island

in the shape of a pyramid called the Benben.

And it was here that the sun god Ra came to Earth

and began life.

When they built the first pyramids,

it seems that they were trying to recreate this Benben stone.

Interestingly, on top of many of the early pyramids,

they actually had a recreation of the Benben stone

on top of them, a capstone,

which was covered in electrum,

which is a alloy of gold and silver,

so that it shone in the sunlight.

All this showing that the pyramids are connected

with the Sun

and gaining the power of the Sun

or the sun god Ra.

[Newman] There's also these ideas that these Benben stones

were actually some kind of power collector.

Some people suggest they attract lightning.

There's different ideas about this,

but it has been suggested in Egyptian tradition

that placing such a thing on top of a pyramid

would almost be like connecting with the solar energy

but also connecting with the cosmos.

[Shatner] Could the great pyramids have been some type

of ancient power plants?

Perhaps clues can be found in the 21st-century research

that presents an extraordinary claim.

[Shatner reads on-screen text]

After analyzing satellite data,

a team of Italian scientists make an extraordinary

yet controversial announcement.

They claim to have identified a vast underground complex

extending beneath the great pyramids of Giza.

[Newman] One of the most fascinating

discoveries that could potentially rewrite the history

of Egypt and the world are the discoveries

that have been made beneath the pyramids on the Giza Plateau.

Now, this is the work of the Khafre Research Project,

using satellites to actually penetrate into the ground

with a mix of other technologies.

What they claim to have found

is a series of shafts

going over 600 meters down into the ground.

And then there's these giant square chambers

and many other chambers and many other systems

across the entire Giza Plateau,

underneath all the pyramids

and even underneath the Sphinx as well.

They're now claiming that there's a whole veritable

underground city beneath Giza.

But then the question becomes: why did they do this?

And we can't obviously tell exactly what's down there

until we fully investigate.

But it would seem that this influenced the positioning

of the pyramids, actually, on the surface.

[Shatner] Could there be an entire city

hiding beneath the great pyramids of Giza?

Only time will tell.

And while Egypt's colossal creations are awe-inspiring,

these remarkable structures represent a mere fraction

of all the enigmatic pyramids found

on nearly every continent on Earth.

[Naunton] Pyramids

have captured our imagination

just because of their sheer monumentality.

The biggest of them are among the biggest buildings

human beings have ever built.

They are monumental, serious achievements.

Very, very beautiful.

That, to me, is absolutely awe-inspiring.

[Collins] Pyramids were built by different cultures

at different times,

with the earliest pyramids probably going back

to the beginning of the third millennium BC.

But I suppose the bigger question is:

why build pyramids?

Was there some reason

different cultures have done this

all over the world for many thousands of years?

We need to know why.

[Shatner reads on-screen text]

Among the ever-shifting sands

of the Nile Valley stands a remarkable achievement--

hundreds of ancient pyramids

that stretch about 150 miles across the desert.

These UNESCO World Heritage sites

contain what are known as

the Nubian pyramids.

[Breidenstein] What often surprises people

is that there are more pyramids in Sudan

than there are in Egypt,

with more than 200 known structures.

Most of them are clustered around El-Kurru,

Nuri, and Meroë.

A few are found at Jebel Barkal, near the sacred mountain.

These pyramids functioned as tombs for the dead

but also a statement of authority

and continuity in ancient Sudan.

Often, there was a offering chapel placed

at the front of these pyramids.

They had a distinct Nubian character to them.

What's really interesting about them is the fact

that they're, like, solid stone constructions.

They don't have any chambers within them,

but they have chambers deep underneath them,

where the kings and queens are said to have been buried,

with staircases around the side of them leading down into them.

[Shatner] Construction on the Nubian pyramids

began around 750 BC

and continued for about 1,100 years.

These steep structures range from 20 to 100 feet tall

and are made from a combination of sandstone,

rubble, and mud bricks.

And the mysterious lost civilization that made them

is known as the Kingdom of Kush.

[Naunton] Kush was a kingdom to the south of Egypt.

They seem to have been very much influenced by the Egyptians.

It flourished from around the eighth century BC

down to the third or fourth century AD.

Um, in that very early time,

eighth century into the seventh century,

Kush became powerful enough to invade Egypt and take it over.

A Kushite king

took control of Egypt

and made himself recognized as the pharaoh.

He was able to maintain control of Egypt.

And, in fact, his successors were as well.

And this line of Nubian kings came to rule Egypt

as the Egyptian 25th dynasty.

And they remained in control for the best part of a century.

But we don't understand

in all the details exactly how this happened.

[Shatner] As powerful as the Kingdom of Kush once was,

much of their story remains unknown

because scholars have yet to decipher

their puzzling system of writing,

known as Meroitic.

But some believe the key to understanding

this mysterious kingdom

could still be hiding beneath one of its pyramids.

[Shatner reads on-screen text]

A team of scientists begin an unprecedented investigation

of the ancient necropolis

that consists of around 20 Nubian pyramids,

including the pyramid of King Nastasen,

the last Kushite king to be buried here in 315 BC.

[Breidenstein] King Nastasen reigned

during a very interesting time of political transition.

The fact that he was the last to be buried at Nuri

and then the Kushite capital was moved deeper in the desert,

that makes his tomb an interesting capsule

of maybe what was happening during this time.

The Nuri Archaeological Expedition began work in 2018

to start excavations at this massive 170-acre site.

We had a possibility

that there was an intact tomb for Nastasen,

and so I was brought on to work with the skeletal remains

that may be found on-site.

[Shatner] Over the centuries, rising groundwater

has left the three burial chambers

of King Nastasen's pyramid completely flooded.

To access the tomb,

an experienced dive team was needed

to explore the pristine and unpredictable environment.

The tomb of Nastasen has remained untouched from looters

due to it being flooded.

The water has acted like a protector for the tomb.

No one's gonna be able to swim and hold their breath

and swim all the way into chamber three

and retrieve these objects.

So it's kept them safe over the last 2,500 years.

[Shatner] What wonders could the flooded pyramid

of King Nastasen still hide below?

In 2019, Justin Schneider became one

of the first people in thousands of years

to enter its unknown depths.

[Schneider] The water in the front of the tomb

is a brownish sand color

from all of the outside

sediments and all the rock falling into it.

You come in through chamber one,

which is a-a long hallway.

Water goes all the way to the top.

Once you go into chamber two,

you can actually put your face out of the water

and you can see inside this tomb.

[Breidenstein] It was a little scary to see

how much of the ceiling had collapsed.

That chamber was pretty chaotic,

but you could still make out the size and shape of that chamber.

And we were finding shabtis,

these small figures that have hieroglyphics on them.

[Schneider] These little shabti figurines,

they're these tiny doll-like carved statues.

They are five to six inches.

They're made of clay.

They're beautiful. They're ornate.

Just touching this stuff is to touch history.

It's-it's incredible.

[Shatner] While the team discovered

a number of small artifacts,

the real prize was believed to be inside the pyramid's third

and final chamber.

[Breidenstein] Within the third burial chamber,

while it was difficult to see,

there was a large rectangular slab

that was about in the middle of the chamber

that we would estimate to be

either a sarcophagus or a burial bed.

[Schneider] You're swimming through this water,

this murkiness,

and then finally getting to chamber three,

the burial chamber.

It was breathtaking to see what you know is a king's burial.

There is a pharaoh, there is a king buried inside of this.

It's a time capsule that's just waiting to be opened.

But we just can't blatantly go in there and start digging.

We have to figure out how to take that out

in order to be preserved.

[Shatner] Unfortunately, before the team could enact a plan

to safely open King Nastasen's sarcophagus,

civil war broke out in Sudan

and all excavations have since been halted.

It is my hope that the political situation can be resolved.

The Nubian pyramids are tantalizing clues

to understand a past in the Nile Valley

that has typically been overlooked

when studying the ancient world.

There's so much more to be discovered.

It's fascinating to imagine the Kingdom of Kush

covered in more than 200 pyramids.

But halfway across the globe,

there is a massive structure that stands alone.

It's the largest pyramid in the world.

And for centuries,

it was hidden in plain sight.

[Shatner reads on-screen text]

In the shadow of an active volcano

stands a massive grass-covered hill

crowned by an impressive 16th-century Spanish church.

And buried below hides something few would expect--

the Great Pyramid of Cholula.

[McNeill] This is an interesting one.

The pyramid of Cholula, its name in Nahuatl

means "man-made mountain."

So there's already an acknowledgement

that this thing is big.

And this thing is really big.

It is, in fact, contrary to many people's expectations,

the largest pyramid in the world.

It's not the tallest.

The Great Pyramid of Giza is in fact taller.

But by volume,

the pyramid of Cholula is the largest pyramid

that humans have ever constructed.

[McCafferty] Scientific archaeology

really began in the, uh...

in the late 1920s with the Proyecto Cholula...

...a project that was directed by Ignacio Marquina.

And Marquina explored the pyramid

through eight kilometers of tunnels

that the archaeologists dug.

These tunnels uncovered murals.

And archaeologists discovered that there were

actually multiple construction phases.

So the pyramid is a-- sort of a layer cake

with platforms that come out from the sides.

All largely unexcavated.

Today, walking through the tunnels,

you absolutely get a sense of the weight

of the pyramid above you.

Because it is massive.

[Jarzombek] The pyramid started out as a smaller pyramid.

Later on, that got covered over

by just sort of putting a new one on top of it.

And then that got covered over.

There are, like, eight or nine layers to this.

And over time, it got bigger and bigger and bigger.

And then when the Aztecs took over,

they had no idea how it got this big.

And it was just as much a mystery to the Aztecs

as it was to us.

[Shatner] While it's believed the pyramid

was first constructed about 200 BC

and later built upon by Mesoamerican cultures

like the Olmecs and the Toltecs,

local legends describe the original builders

as monumental in stature.

It's one of the most fascinating traditions

relating to the pyramid of Cholula

is that of the Quinametzin giants.

This was this very ancient era

going back potentially thousands of years.

These giants, who were said to be up to 12 feet tall,

constructed the Cholula pyramid.

Because it is so vast, so big,

no one could imagine how any humans

could've constructed it themselves.

[Shatner] While it's intriguing to think that giants built

the first iteration of the Great Pyramid of Cholula,

the legend itself suggests that, even centuries ago,

the structure was not only hard to explain

but also a place of profound and ancient reverence.

[McNeill] This has been a temple at every stage.

So I think one of the things we see here is

a recognition of the holiness or the sanctity of this place.

That a temple followed by another temple

followed by another temple,

being topped with a church.

In Cholula, we see this unintentional

collaborative process that builds upon the sanctity

of this unbelievably holy place.

[Shatner] Cholula's importance to many Mesoamerican cultures

has led to another fundamental mystery:

why was the largest pyramid ever constructed

hidden under piles of dirt?

[Schoch] Some people suggest

that it wasn't necessarily just abandoned

but the Aztecs and the Indigenous people,

knowing that the Spanish were coming to conquer them,

they wanted to cover it up.

So there are some suggestions

that they may have tried to plant

plants on it, hide it, disguise it.

By the time the Spanish came,

apparently they thought it was a natural hill.

They did not recognize it as a pyramid.

[Shatner] Was the Great Pyramid of Cholula

deliberately disguised to hide it from Spanish invaders?

And if so, what were its guardians compelled to protect?

[Collins] According to legend,

right at the base of the Cholula Great Pyramid,

there was a natural spring.

And it is seen as the waters of life

emerging from the place of first creation.

It was said that Cholula was built

shortly after the time of a great flood,

a deluge that had ended a previous world age.

So, did this really happen?

Is this a memory of some of the first people to create

the earliest stages of this pyramid?

Very possibly.

[Shatner] Could the Great Pyramid of Cholula

be built atop a powerful sacred spring?

It's a belief that was still in existence in 1519,

when Spanish invaders led by Hernán Cortés

first reached the ancient city of Cholula.

[McCafferty] One of the myths

from the time of the conquest

was that the Indigenous allies that were accompanying Cortés,

uh, on the attack on Cholula

were afraid of entering the city

because they believed that anybody attacking Cholula

would be washed away when the pyramid burst forth

with earthly waters.

But we don't know. Chalk it up to a mystery.

[McNeill] We don't know who built it.

We don't know the details

of their mythology or their cosmology.

But we see this recognition of sacredness in this location.

It's significant that what was built here at every stage

was a temple.

It's common knowledge

that the Cholula pyramid was built to be

a sacred religious site.

And it successfully served that purpose

for over a thousand years.

But the same cannot be said for a collection

of rectangular pyramid-shaped structures

found in the remote Canary Islands

whose very existence

has baffled scientists for decades.

[Shatner reads on-screen text]

More than 200 miles

off the northwest coast of Africa,

this remote island rises from the Atlantic Ocean.

And here stand six enigmatic structures

made of stacked volcanic stone

known as the step pyramids of Güímar.

These are pyramids that there's a lot of controversy about.

People have suggested that these are

very ancient pyramids, a very ancient site.

So, there's been a lot of mythology

and speculation about them.

And modern legends have developed about these pyramids.

But these pyramids may only go back to the 19th century.

They may be nothing more than the result

of people clearing their fields

and stacking them up and making pyramids out of them.

[Shatner] So, just how old are these mysterious structures?

Well, some believe the most compelling clue

could be their connection to the summer solstice,

the longest day of the year.

[Collins] These pyramids are perfectly aligned

towards sunset at the time of the summer solstice.

And this was actually confirmed by archaeoastronomers

under the leadership of Juan Belmonte,

who actually lives on the Canary Islands.

So, this is a very special phenomena,

and it could be behind why

these pyramids were constructed in the first place.

[Shatner] Were the Güímar Pyramids built

to mark the summer solstice?

If so, the theory that they were simply stacked

by 19th-century farmers after clearing their fields

seems too simple an explanation.

And more intriguingly,

some claim the pyramids on Tenerife

share striking similarities to other pyramids

around the world.

[Phillips] There are other alignments to stars

exactly as we find in the Egyptian pyramids,

and we also find in the pyramids of Central America.

The native people who lived on Tenerife

before the Spanish arrived in the 1500s

had seemingly been living in isolation

for thousands of years.

How could they possibly

be building the same kind of things as people

either side of the Atlantic,

unless there was some connection between them?

[Shatner] Are the Pyramids of Güímar connected

to other pyramids around the world?

Well, according to one world-famous explorer,

the link could be more significant than we've imagined.

[Bradshaw] Thor Heyerdahl was a Norwegian explorer

who was most famous for his Kon-Tiki voyage,

which aimed to show that people could use quite simple rafts

to conduct long-distance sea travel.

Heyerdahl traveled to Tenerife in the 1990s

and was particularly intrigued by the idea

that ancient navigators would have had

a very good understanding of the stars

to help them navigate.

And that as they traveled,

ideas would be spread around geographically.

So, mapping that theory onto the Pyramids of Güímar,

Heyerdahl thought, "Well, if there are pyramids here

in the Canary Islands,

which is between Europe, Africa and the Atlantic Ocean,

why can't there have been this sort of cross-pollination

of ideas around the world?"

[Shatner] Did pyramid builders share their knowledge

throughout the ancient world across vast oceans?

It's a fascinating theory that may suggest

that the Pyramids of Güímar

really were constructed in antiquity

by the original inhabitants of the Canary Islands.

A now-extinct culture known as the Guanche.

[Schoch] The Guanche are Indigenous people

to the Canary Islands.

They're very mysterious on many levels.

Modern scholarship suggests

that they actually are an offshoot from North Africa

that got to the islands in the first millennium BCE,

living there until the Spanish ultimately

conquered the Canary Islands in the 15th century.

The Guanche had a lot of what appears

to have been advanced knowledge in terms of mummification

and the rituals they carried out.

They lived in caves and stone huts.

But there's this whole modern, should we say,

hypotheses and legends and suggestions that somehow,

they were descendants of Atlantis,

the legendary civilization

that was decimated by natural events.

Bottom line is, the Guanche are a real mystery.

They're something that needs more study.

Um, absolutely fascinating.

[Shatner] Could the early inhabitants

of the Canary Islands have some connection

to the mythical island of Atlantis?

It's fantastic to consider.

But more importantly, were the Guanche people

once part of a network

responsible for the proliferation

of pyramids around the world?

[Newman] The builders of these pyramids on Tenerife

were pretty sophisticated.

They were building these quite elaborate

black stone constructions.

They were aligning them

to specific movements of the Sun,

and the stars as well.

It does appear that

there was a common architectural language

being spread across the world in ancient times.

We find very similar pyramid styles

in all these different places.

Often, step pyramids.

And it was almost like an ancient code

being embedded within these permanent structures

in all these different parts of the world.

[Schoch] So, this gets into the argument of,

was there knowledge being passed around?

We don't know. There's just a lot

of mysteries about pyramids, when it comes right down to it.

Could the astrological alignments

found at the Canary Island structures

be evidence of a universal pyramid code

spread around the world?

Perhaps time will tell.

Which may also be the case for a controversial claim

that a powerful pyramid lies hundreds of feet below

the Alaskan tundra.

[Shatner reads on-screen text]

With over 57 million acres of designated wilderness,

which is more than all other U.S. states combined,

and with civilization found in less than one percent

of its total landmass,

there have been many claims as to

what's hiding in this remote frontier.

But perhaps one of the strangest tales

revolves around an alleged "Dark Pyramid,"

obscured beneath Alaska's frozen wasteland.

[Ricksecker] The Dark Pyramid is a presumed pyramid

that is hidden under the ice and tundra

of remote areas of Alaska.

This pyramid is near Mount Denali,

in the heart of what's known as the Alaska Triangle.

The Alaska Triangle is a very anomalous area,

which stretches from Juneau in the south

to Anchorage in the middle and Utqiagvik at the top,

formerly Barrow.

And it's much like its namesake, the Bermuda Triangle,

in which there's, uh, a lot of strange activity

that happens in this area,

with the Dark Pyramid right at the heart of it.

[Shatner] If a pyramid is hiding beneath the ice

in one of the most remote regions of Alaska,

how would we even know about it in the first place?

Well, according to the story,

it was detected in 1992,

when China was testing weapons of mass destruction

beneath a dry lake bed known as Lop Nur.

[Ricksecker] In 1992, the Chinese government

initiated underground nuclear testing.

The United States knew about this,

our geologists set up a bunch of seismic equipment

to be able to detect

the shock waves from this explosion.

And when that explosion occurred

and the seismic equipment was going off,

they discovered this strange pyramidal shape

near Mount Denali in Alaska.

[Shatner] To this day, no public record

has confirmed the discovery of a buried pyramid beneath Alaska.

But some are convinced that the lack of evidence

is purely intentional.

Because it's said that when news

of the Dark Pyramid was released,

it was immediately covered up.

[Ricksecker] It was broadcast

on the local news, Anchorage channel 13,

that this had been discovered.

And there was a young service member Doug Mutschler,

in the Army, who saw this particular broadcast.

And he was so fascinated by this.

[Howe] Doug Mutschler worked in counterintelligence

for the Army in Fort Richardson in Anchorage.

That particular night, there were 40 guys,

and they're watching channel 13, and it shows

a pyramid structure underneath the ground in Alaska.

So, he approaches the general manager at channel 13.

The general manager said, "I don't know

what you're talking about."

[speaking inaudibly]

[Howe] And Doug said he started arguing

with the general manager.

"I was with 39 other guys.

40 of us, we watched this."

And the general manager said, "Well, you are mistaken."

Doug turns around to leave, and coming around a corner

is a man who took ahold of his arm and says,

"I know what you're talking about.

Yes, we have that film,

but we have been told that we are not

to broadcast it or talk about it anymore."

[Shatner] Was the story of the Dark Pyramid

deliberately buried?

And if so, why?

For some, the answer is simple:

the Dark Pyramid isn't really a structure at all

but a 550-foot-tall

top secret machine.

[Ricksecker] There are a few different theories

about the Dark Pyramid.

One is that it was some sort of

ancient power plant that has been hidden

under the surface of Alaska.

When we look at the Great Pyramid of Giza,

one of the suggested ideas of what it was,

was a possible ancient power plant.

Now, the Dark Pyramid is supposed to be taller

than the Great Pyramid of Giza.

So, how much more energy than the Great Pyramid of Giza

could this Dark Pyramid be harnessing?

[Howe] Why would a 550-foot

solid black pyramid be underground?

What is it doing in the backcountry of Alaska,

and how long has it been there?

I think, there's no question,

the government of the United States

didn't want anybody to know anything

about this Dark Pyramid.

Did they know about the pyramid before

the 1992 Lop Nur bomb test?

Oh, I think so.

[Shatner reads on-screen text]

As NASA's Mariner 9 spacecraft

photographs the Red Planet,

it captures something unusual in a region called Elysium.

Formations that appear, at least from orbit,

to resemble pyramids.

[George Haas] One of the images that they took

in the Elysium area of Mars,

uh, actually showed what appeared to be

three-sided pyramids.

They were noticed by a scientist

by the name of Mack Gipson.

He actually had a science paper published

in Icarus journal titled "Pyramidal Structures on Mars."

So, early on, there was a lot of scientific investigation.

Real scientists were looking at Mars saying,

"Ooh, possibly there's structures here."

Structures that looked artificial.

[Shatner] Could there actually be artificial pyramids on Mars?

While it sounds far-fetched,

in 1976, NASA's Viking 1 orbiter

photographed yet another strange formation

that researchers named the D & M pyramid.

[Schoch] The D & M pyramid

looks like a five-side pyramid, which is unusual unto itself.

Other pyramids in Martian photographs

look like they have three sides.

But people made claims these must be artificial structures

that came from some, you know, civilization on Mars.

And I'm not opposed to the possibility

of there being extraterrestrial, sophisticated civilizations,

but we have to be very careful

when we think we see artificial pyramids.

Nature also forms pyramids

and pyramidal-type structures.

You can have symmetry in nature.

As a geologist, I see symmetry all the time.

What are some of the most symmetrical things?

A pyramid.

[Shatner] Without visiting the Red Planet ourselves

for a closer look, it's impossible to know

whether the alleged pyramids on Mars

are just natural formations or artificial constructions.

But with so many mysterious pyramids

that continue to fascinate us right here on Earth,

perhaps it's simply part of human nature

to become enamored with these iconic,

awe-inspiring structures.

Humans have always wanted to build

the biggest thing that lasts for the longest.

So, if you're an ancient culture,

this is a pyramid

because you have the stable structure

which allows you to build quite high.

I therefore think that the fact you have

pyramids in Mesoamerica,

in the Canary Islands and in Egypt,

is just a reflection of how different cultures

come up with similar solutions to similar problems.

How do we build high? How do we build big?

A pyramid is your answer.

[Jarzombek] Each of these things that we call pyramids

has a code.

Whether we understand that code or not,

that's part of what the scholarship

is trying to sort of figure out.

How were these places used?

And that's the stuff that scholarship is made of.

But whether we know the code or not,

that's another question.

Could pyramids really exist on other planets?

Who knows?

For now, it's the remarkable structures we have here on Earth

that continue to captivate us

and challenge our understanding of human history.

The Giza Plateau may be the best-known pyramid complex,

but it's only one example

of this extraordinary engineering

found all around the world.

Will we ever know how

and why some pyramids were built?

The secrets surrounding these mysterious structures

are innumerable, and may forever remain...

...unexplained.

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