Tonight... They've been called
the world's greatest archeological enigma.
AARON HINKLEY: Everyone focuses on the Nazca Lines
because of just how mysterious they are.
LAURENCE: 2,000 year-old drawings so massive,
they can only be seen from the air.
But what are they and why were they created?
FORREST BURGESS: We know they didn't just appear
out of thin air, but there is virtually
no historical record of previous societies in Peru.
Now, we examine the top theories behind their mysterious origins.
Maybe the Lines were ritual battlefields,
but I don't think that's all they ever were.
They found a collection of severed heads,
and this really suggests that the Nazca Lines
could be connected to ritual human sacrifice.
This is why we think the Nazca Lines
may have been repurposed.
LAURENCE: Can new research finally unravel their secrets?
Researchers make a shocking discovery
and, if this theory is correct,
they might have solved one
of archeology's greatest riddles.
What is the true purpose of the Nazca Lines?
♪ ♪
LAURENCE: September, 1926. Nazca, Peru.
Archeologist Toribio Mejia Xesspe
leads an expedition in the Peruvian desert.
Xesspe and his team have been drawn here by a discovery
of a giant underground acropolis full of hundreds of mummies.
When most people think of mummies,
they tend to think of Egyptian mummies,
but, in fact, the oldest mummies in the world
are from Northern Chile and Southern Peru.
LAURENCE: Dating back over 7,000 years,
they're known as the Chinchorro mummies.
Xesspe examines some that are wrapped in thick layers
of expertly-woven cotton textiles,
covered in vibrant images of mystical figures and animals.
LAURENCE: One day, while taking a break
from his work, Xesspe hikes up a nearby hill.
He gets to the summit, looks out over the desert plain,
and he's met with a stunning sight
he can barely believe.
Xesspe sees a series of thick lines
carved into the rocky desert.
Some stretch as far as his eyes can see.
These lines are incredibly long, perhaps miles,
and they're straight as a ruler.
At first, he thinks they're trails or roads,
but he notices that several of them plow right
over the mountains and other rugged terrain.
Not exactly what you would do if you were building a road.
Eventually, he realizes a lot of these are forming
geometric shapes, you know, kind of standard rectangles, spirals,
squares, triangles,
some of them as big as a football field,
to put it in perspective.
LAURENCE: Intrigued, Xesspe puts his mummy research
on hold to investigate.
One of the things Xesspe realizes would be useful is
to get a better look at these from higher up.
So he calls in the Peruvian Air Force
to get that overall aerial view.
They can fly over it, see what's really going on.
When they reach altitude,
the pilots can't believe their eyes.
The lines and shapes cover an area
that stretches for hundreds of square miles,
far beyond what Xesspe originally saw.
There are spirals, zigzags...
There are drawings of birds, spiders, monkeys,
immense in scale.
These images are impossible to see
in their entirety from the ground,
so the pilots realize they're probably the first people
to ever truly witness the scale of this unusual formation.
LAURENCE: The strange markings become known as the Nazca Lines.
When you look at how many Lines are actually there,
it's an incredible number.
Over 800 Lines total, hundreds of geometric shapes
and at least 100 animals are present in this area.
Some of the Lines are thousands of meters,
all the way up to 25 miles, and this is quite incredible.
The precision of these Lines is super impressive,
even by modern survey standards,
because many of them are just dead straight.
FORREST BURGESS: And for 100 years now,
ever since Xesspe first spotted them,
they've been a mystery.
Who made them? When were they made?
Why? What's the purpose of them?
LAURENCE: Initially, it's believed
the Inca are responsible.
Beginning in the 12th century, the Incan Empire
eventually rules a large area of South America
until Spain conquers them in the 1530s.
But scientists eventually date the Lines to between 300 BC
and 800 AD, which means all of them
predate the Incas.
LAURENCE: In fact, some of the Lines
are almost 2,500 years old.
We know they didn't just appear out of thin air,
but there is virtually no historical record
of previous societies in Peru because the Incas,
and later the Spanish, made it a policy to suppress
and destroy every trace of the cultures they conquered.
And so who built them remains one of the biggest mysteries.
LAURENCE: But how they were made is much easier to answer.
The ground is covered with a desert varnish.
It's these small pebbles, rocks that have
this black patina on them.
When you scrape away this darker layer,
you reveal a lighter layer underneath.
It's a stark contrast, like a negative image.
So that's the method they used.
LAURENCE: The region is also one of the driest on Earth.
It receives only a millimeter of rain a year,
and because there's no rain in this area,
these Lines were able to survive for thousands of years.
LAURENCE: After 13 years researching the Lines,
Xesspe presents his findings at a conference in 1939.
This conference is the first time that people
from outside of Peru have heard of these Lines.
Xesspe's work has been mostly cataloging and measuring them.
He doesn't suggest an overarching purpose
for the Lines, but it gets a lot of people excited.
LAURENCE: Among those intrigued, a scholar named Paul Kosok.
Kosok is a history professor from Long Island University
in Brooklyn, and he's in Peru studying pre-Columbian society
and culture, particularly focused
on their irrigation systems.
LAURENCE: Inspired by Xesspe's work,
Kosok travels to Nazca to try and solve the puzzle.
FORREST: In June of 1941, he's charting several
of the shapes in the vast desert plain.
As he contemplates their purpose, he glances up
at the setting sun and is struck with a sudden epiphany.
Kozok realizes that the Line he's charting
points directly at the sunset over the horizon.
LAURENCE: Kosok has a revelation about what these lines could be.
It's late June in Peru, just about the time
of the winter solstice in the Southern Hemisphere.
It strikes him that these lines could be
an astronomical calendar.
♪ ♪
Kosok returns to Lima with this incredible story
of discovering what might be the largest astronomy textbook
in the world, etched into the sands of the desert.
LAURENCE: There, Kosok consults with a German mathematician
named Maria Reiche, to figure out
more specifically what the calendar is tracking.
So Reiche works at the National Museum of Lima
and is a restorer, and she hears about this and really
gets interested in exploring in much more detail
how these figures could work
from an astronomical perspective.
LAURENCE: On her first trip to Nazca in 1941,
Reiche identifies 16 lines
that point directly at the rising
or setting sun on the dates of the solstice.
Reiche also thinks she knows why the Lines' creators
might have made this calendar to begin with.
One of the things Reiche did really well
was track a large number of correlations
between the different figures and different elements
of astronomical importance.
Two examples are a line on the spider figure that points
to Orion and a set of lines
on another figure that point to the Pleiades.
Many ancient civilizations are based
around agriculture and farming,
and knowing when to plant or when to harvest
is vitally important.
Often, these times would coincide
with atmospheric patterns, like rain.
AARON: But what do you do in a place where it never rains?
FORREST: Most of this region's water comes from periodic runoff
from the surrounding mountains.
So a farming culture with an environment
with virtually no rainfall would rely heavily
on a celestial calendar to determine planting times
for their survival.
When that water comes,
you need to be ready.
MICHAEL DENNIN: So one constellation you can use
in this fashion is the Pleiades.
When they show up in November, you know you're really close
to the rainfall up in the mountains.
You're about to get your runoff,
so you start your planting season,
and when the Pleiades leave the sky later in the year,
that's when you know it's time to start your harvest.
LAURENCE: Reiche reports her findings to the press,
providing the first published theory on the Nazca Lines.
AARON: To this day, Reiche's interpretation
of the Lines dominates the public's perception of them.
She's dubbed the Lady of the Lines.
FORREST: There's plenty of reason to believe this theory,
because there are examples
of many other prehistoric cultures
of earthworks being constructed to aid
in astronomical sightings and calendars.
LAURENCE: The famed Stonehenge may be one such example.
FORREST: In the 1960s,
an astronomer named Gerald Hawkins
calculated the positions of its standing stones
using an early IBM computer and announced that the monument
was designed to predict astronomical events.
His work was a sensation around the world,
and inspired a new branch of science,
known as archeoastronomy.
LAURENCE: In 1968, Hawkins visits Nazca to study the Lines,
using the same computer matching technique.
MICHAEL: In particular, what Hawkins looks at
is 21 triangles and 70 or so lines,
and really asks, "Okay, how well correlated
are these with astronomical phenomena?
His conclusion? The connections Reiche found
were only coincidental.
One of the issues is that there are just
so many of the Lines and in such a large variety
and in so many directions, that, to suggest all of them,
or even most of them, are connected to astronomy
is a clear stretch.
MICHAEL: Reiche and Kosok, when they see the findings,
they don't disagree with them.
I mean, the computer findings are pretty solid,
but they do point out
that this isn't necessarily conclusive.
It doesn't rule out that some of the Lines
aren't astronomical.
FORREST: They believe there are some alignments, which are done
on purpose to be used as a celestial calendar,
but there must also be a much larger and grand purpose
to the design that they haven't figured out yet.
LAURENCE: When Peruvian archeologist
Toribio Xesspe discovers the Nazca Lines in 1926,
the first thing that strikes him is their incredible scale.
MICHAEL: When you look at these shapes and features,
they're so huge, they can only be viewed
from above and very high in the sky.
So this does mean that the culture that built them
would actually never be able to see them directly.
FORREST: We know there weren't planes or other flying vessels
2,500 years ago, when the Lines were first created,
but somehow these people decided to craft designs
meant to be seen from what, to them,
would have been an impossible viewpoint.
It doesn't make sense.
LAURENCE: Unless the Lines were designed for another purpose.
In 1968, Swiss author Eric Von Daniken
claims he knows the reason.
The Lines aren't built for anyone on Earth.
Instead, they're built as a landing guide
to an extraterrestrial species
that once visited the Nazcans from the heavens.
♪ ♪
One of the first Europeans to see the Lines is
a magistrate named Luis de Monzon in 1586.
FORREST: He initially suspects that they are traces
of ancient roads, which, of course,
we know isn't true these days.
CAROLINE CORY: When he asks the locals about them,
he's told of a legend.
In very old times, the Nazcans were visited
by people they called the Viracochas.
They referred to as saintly persons.
The locals tell De Monzon that the paths
were actually built for them.
LAURENCE: Viracocha is also the name of a Nazcan god.
This deity dates back to around 3000 BC,
and the legend says that he came from the sky in a golden boat,
from the other side of the Milky Way,
to be specific.
In the oldest depictions, he's pictured
with a cone-shaped skull and only four digits
on his hands and feet.
LAURENCE: Von Daniken believes these legends are a reference
to extraterrestrials.
MICHAEL: One of Von Daniken's key thesis and beliefs
is that the ancient people saw these extraterrestrials,
these aliens, as gods.
FORREST: Von Daniken believes that when the Viracochas,
or aliens, first visit,
they teach the Nazca people how to make these Lines.
FORREST: The earliest Lines are built as a landing pad
or navigational marker,
basically an airstrip for these alien ships.
We don't know if these aliens ever made any return visits,
but Von Daniken believes that eventually they stop coming,
and the Nazca decide to get creative.
FORREST: They want the Viracochas
to return back as soon as possible,
so they start building more and more elaborate Nazca Lines.
LAURENCE: Von Daniken's 1968 book,
"Chariots of the Gods," turns the Nazca Lines
into an international phenomenon.
MICHAEL: When Von Daniken first came out with his book,
this really generated a lot of interest,
a lot of excitement, a lot of buzz.
It was a very, very intriguing idea
that maybe aliens had visited.
FORREST: And, in fact, some people look
at one of the Nazca geoglyphs in particular, and believe
it may prove Von Daniken's theory.
LAURENCE: Known as The Astronaut,
this figure covers nearly 100ft of a hillside,
overlooking the desert.
Some call it The Astronaut because it looks like
it's wearing a space helmet,
which, of course, is a modern interpretation.
Most historians refer to him as the Owl Man.
AARON: It's a humanoid figure, but clearly not entirely human.
It features large, round eyes, and it seems to be
waving hello to someone in the skies.
CAROLINE: A thousand years after the creation
of the Nazca Astronaut, the Inca build a statue
of Viracocha in Cusco, raising his right hand,
much like The Astronaut.
Scholars believe the Nazca Astronaut
could be an image of the same god.
AARON: We don't currently have any way to know
if the Nazca Astronaut is an alien.
There are no records from this society,
apart from the Nazca Lines themselves.
LAURENCE: But one ancient practice
might offer more insight.
FORREST: Remember those ancient Peruvian mummies
Xesspe was examining?
Well, shockingly, many of them have elongated skulls.
Today, it might be seen
as a strange and disturbing look,
but it's believed that the natives did this on purpose,
by attaching wooden boards to their infants' heads.
Several mummies are even found
with these boards still attached.
LAURENCE: The question is, why?
We've seen Viracocha represented with an elongated head,
and many representations of aliens
with a similar head shape.
Well, perhaps they're trying to emulate the appearance
of their gods, who had similar features.
LAURENCE: A 2017 discovery takes this claim a step further.
FORREST: Dr. Konstantin Korotkov,
professor of biophysics
at St. Petersburg Federal University,
shows the press these mummies
that he believes aren't human at all.
They look like they're covered in plaster,
but Korotkov explains,
"This is just calcification and protective material."
They have elongated heads, large round eyes,
and just three digits on their hands and feet.
He calls it, quote, "Another creature,"
different from anything else in our fossil record.
These mummies are made famous by a web series
claiming to investigate their authenticity.
Millions of people watch as stupefied scientists
declare them to be the genuine article.
The body they examine is indeed organic,
and it dates back 1,700 years.
LAURENCE: But when another team of scientists
inspects the mummies, they're proven to be fake.
MICHELE KOONS: They discovered that these were mummies
that were modified for this hoax
and really turns out to be quite disturbing.
FORREST: These bodies are made from real indigenous mummies,
which have been mutilated to make them look like aliens.
Their ears and noses are sliced away
and the alterations are covered up
with a white plastery powder.
But the other mummies with the elongated heads
remain genuine.
Those are humans who most definitely
gave themselves an otherworldly appearance.
Why? We don't know.
AARON: I think everyone would like to know the answer
to that question.
Maybe they were trying to connect with another culture
that once visited them from above.
Or maybe they just heard stories of some visit
from long ago and were inspired.
LAURENCE: Nazca, Peru, is home
to two incredible ancient phenomena,
the Nazca Lines and a necropolis
of South American mummies, several thousand years old.
FORREST:veryone focuses on the Nazca Lines
because of just how massive and perplexing they are.
But we can't lose sight of the mummies,
because the two may be intricately linked.
AARON: Mummification here dates back 7,000 years.
That's a full 2,000 years
before the first Egyptian mummies.
MICHELE: In Egypt, they used different techniques
to dry out the body before they would wrap it.
In this region, they didn't do anything artificial.
The mummies were able to preserve
because this desert environment is so dry.
In fact, some of these mummies are way better preserved
than what we even see in ancient Egypt.
FORREST: Dry conditions are one part of the reason,
but the other is the technique they used.
While the Egyptians used fine linens, the Nazca mummies
are wrapped in very long, thick cotton and wool textiles,
which are embroidered with a skill and quality
that's unmatched by any other civilization.
LAURENCE: In 1983, Swiss historian Henri Stierlin
thinks he knows their secret.
FORREST: Stierlin is an art historian,
and he realizes what it would take for these ancient people
to craft these textiles.
They would need a lot of space and huge long looms,
essentially an ancient version of a factory,
to churn out this incredible amount of cloth.
He looks around at what they have nearby
and he determines the Nazca Lines
might be the place.
♪ ♪
LAURENCE: Stierlin writes a book
called "Nazca, the Key to the Mystery,"
which details his theory.
AARON: One of the most stunning discoveries
about these mummy wraps is that they are made
from a single piece of cotton thread,
which can be dozens of miles long.
This idea of a single thread is reflected in the way
the Nazca Lines are created too.
They're made with a single line,
which starts and ends in the same spot.
FORREST: So first they need to make very long threads.
Stierlin believes they use the wide clearings
within the geometric shapes as sacred spaces
for spinning the cotton fibers into these threads.
As the threads are made, Stierlin thinks the weavers
would lay them out along the Nazca Line's animal designs.
LAURENCE: According to Peruvian beliefs,
each animal carries a different significance.
FORREST: So, depending on who they're burying,
they would lay the thread in a different Nazca Line
to infuse it with the power of that family's chosen animal.
For instance, the whale provides success in fishing.
The hummingbird provides fertility.
LAURENCE: As far as the actual weaving, Stierlin thinks
this takes place within the Nazca Lines themselves.
So Stierlin had this idea that the Nazca Lines
acted as a giant loom,
because there are these posts within the Nazca Lines,
the people would take the thread and wind
back and forth over the Lines to create the textiles.
FORREST: There were posts found at the Nazca Lines.
That's actually how scientists are able to date them
in the first place.
They test the remains of organic wooden posts
discovered nearby.
Stierlin believes these posts could have been
the framework to support this giant loom system.
LAURENCE: Stierlin also finds a connection
in the drawings themselves.
MICHELE: So the designs on the mummy textiles
are very similar to what we see in the Nazca Lines,
a similar array of animals and plants.
FORREST: These ceremonial shapes might have been a part
of the entire process, from the weaving
through to the end of the mummification.
One single mummy shroud could have over
a million stitches on the main panel,
and another 800,000 or so on the borders.
This is a huge collaborative effort.
Making the mummies must have been a very sacred
and important process to these people.
So why not build a sacred and important
site to do it?
AARON: The Egyptian mummies were preserved
and wrapped by priests and elaborate rituals
inside impressive temples.
This could have been a prehistoric version
of the same thing.
LAURENCE: According to Stierlin's theory,
the operation may have expanded beyond the mummies.
♪ ♪
FORREST: The Nazca Lines mummy factory
may have eventually become a textile factory,
serving the entire Andean coast and parts of the highlands.
AARON: It's interesting because while you can't grow
many things in this environment, you can grow cotton.
It's one of the only useful crops they could have had.
FORREST: You have to wonder, how did they survive?
Well, if this was a place that could abundantly
manufacture cloth, they could have traded it.
MICHELE: But Stierlin's theory is really based off
of a lot of speculation.
There's no archeological evidence
that any weaving was done on these Lines.
He probably saw the posts and just had this idea
because textile production is so important in the Andes,
and textiles, in fact, were more important
than even some of the precious metals, like gold.
LAURENCE: But a new discovery in 1987
challenges Stierlin's theory.
About two miles away from the Nazca Lines,
up on a high plateau,
is a ceremonial center called Cahuachi.
An Italian archeologist named Giuseppe Orefici
has been in charge of excavations there since 1984.
He's working closely with an American archeologist,
Helaine Silverman.
FORREST: At Cahuachi, Silverman and Orefici have found
lots of chambers that we now believe to be workshops
for making textiles,
with remains of weaving materials found there.
When Silverman first publishes her work
in the "Journal of Field Archeology" in 1988,
she finds that Cahuachi is the center for the production
of these elaborate costumes worn by the Nazca priests
and where the rituals are performed.
In other words, Cahuachi is the mummy and textile factory,
not the Nazca Lines themselves.
LAURENCE: But some believe there's still a connection
between the two locations.
FORREST: The Nazca Lines might not have been
a mummy factory or textile factory,
but they could have been a place to reflect
while that process was happening nearby.
The entire area, both the Lines in the valley and Cahuachi,
perched above, was most likely a place of pilgrimage
for natives throughout the region,
a kind of religious tourism site
which included a funeral parlor and textile trading.
Visitors to Cahuachi would have had a fine view
of some of the Nazca Lines below,
and I don't think that's a coincidence.
♪ ♪
Many scholars have studied the Nazca Lines
and speculated about their mysterious designs,
but it's not until 2019 that a Japanese research team
takes a closer look at some of the animal patterns.
Their findings unlock a new possible theory
surrounding these shapes.
MICHAEL: The animals represented in the Nazca Lines
are referred to as biomorphs.
There's over 70 of these.
They represent a wide range of animals,
insects like spiders, monkeys, dogs,
and a wide range of birds.
FORREST: The animals range in size from about 50ft long
up to over 1,200ft, almost as tall
as the Empire State Building.
For about 100 years after these were first discovered,
no one really thought carefully about the animals.
They just classified them and noticed,
"Oh, there's animal biomorphs."
The reality is that these animals are shocking
because they don't exist in this area.
And so really asking the question, "Why these animals?
Why here?" Becomes critical.
LAURENCE: Researchers from Hokkaido University in Japan
attempt to answer these questions.
For the first time ever, these Japanese researchers
take a scientific approach to classifying
the species depicted in the Lines.
They want to identify precisely what species each drawing
depicts and where it comes from,
and then maybe they can find
some sort of logic or pattern to figure out the reason.
MICHAEL: So one of the exciting things is there's at least
18 species that they're able to identify.
There are a handful that they actually
just can't associate or identify a particular species for.
FORREST: Along with the rather obvious monkey
and llama, they identify a frigate bird,
a pelican, a guano bird, and even a killer whale.
The hummingbird, they identify it
as a hermit hummingbird, a species that lives
only in the tropics and subtropics,
far to the north and east.
The animals that the Japanese classify are all from places
with lots of water, like the coast or rainy jungle.
So, sure enough, they seem to be identifying a pattern,
and the team believes that water is the key to understanding
the purpose of the Lines.
LAURENCE: Throughout history, early civilizations
rely on an abundance of water to grow food,
but the dry desert conditions of the Nazca region
offer almost none.
FORREST: The very reason these Lines have survived
so long is because the area is so dry.
It only gets rain for maybe 20 minutes a year. 20 minutes.
So what do you do in a place where you don't get any rain,
yet you desperately need it?
For many ancient societies, you pray.
♪ ♪
The Nazca are a priestly society,
a deeply religious society.
We know this from the huge religious complex at Cahuachi,
which is like the Vatican for the Nazca people
and the whole coast of Peru.
The geoglyphs that surround it seem connected
to the complex and the rituals performed there.
And the Japanese team believes all of it is centered
around begging the gods for rain.
CAROLINE: The location of Cahuachi is not an accident.
There's actually a river that runs through the area
and across this stretch of desert,
the river runs underground.
It only emerges above ground again as it enters the lowlands,
right on the spot where Cahuachi's located.
This is where the water is given back to the people.
And so this is where they establish
their most important pilgrimage shrine.
LAURENCE: According to the Japanese team,
many of the Nazca Lines are arranged
in a path that leads directly to Cahuachi.
They're guiding the people to their sacred place
for water rituals.
All along that pilgrimage route, they would be saying
their prayers in the hopes that these mystical animals
swould bring along their region's rain.
Keep in mind, they're not actually praying for the rain
to fall in the desert, that won't help them.
They're praying for it to fall in the surrounding highland
and coastal areas, where they plant their fields.
CAROLINE: They're also praying for the rain
to come peacefully.
The climate along the Peruvian coast
can be unpredictable, and sometimes catastrophic,
with wild deluges that cause landslides and flooding,
wreaking havoc on the farmers.
So the whole belief system with this pilgrimage
along the Nazca Lines is centered around creating
a friendly, working relationship
with the gods who control the weather.
These gods are invoked and pleaded with
within the sacred spaces of Cahuachi and the biomorphs.
♪ ♪
LAURENCE: The team identifies the same species on rock art,
ceramics and textiles from the area.
ALEXEI VRANICH: They even made musical instruments
out of pottery.
FORREST: It must be quite an elaborate
and celebratory process.
You can imagine hundreds of people in colorful costumes,
performing ritual processions or dances along the Nazca Lines,
accompanied by drums and panpipes.
It's quite a spectacle.
♪ ♪
LAURENCE: There seems to be one more connection
between the Lines and water.
The last thing they find is that there are
several rock altars at the edges of some of the clearings,
right by the Nazca Lines,
and inside the altars there are crayfish claws,
crab skeletons, mollusk shells, the remains of sea creatures
here, in the desert, at 4,000 feet above sea level.
That's a bit surprising.
They're bringing these materials
from the largest body of water,
the ocean, as a way of asking the gods for water.
Once again, this supports the Japanese theory.
The Nazca Lines were a place for pilgrims to journey
from all around in the hopes of summoning
their most sacred resource.
LAURENCE: In 2019, Japanese scientists revealed
their belief that the Nazca Lines
were created as a prayer for rain,
a plea that unfortunately failed.
In the early fifth century,
this culture suffers their most extreme drought of all.
It's so bad that Cahuachi is abandoned.
There's no more sacred city for their rain and water rituals,
no place for a pilgrimage.
But after the drought, there are still artifacts
and human remains that suggest people
were still coming to the Nazca Lines.
So I think when you start to make theories
about the Nazca Lines and their purpose,
you have to split them into two distinct periods.
What were they used for before the drought
and what were they used for after?
I think before the drought,
the 2019 theory about the prayers
for rain is probably one of the best options.
That seems to check all the boxes.
LAURENCE: As for their use after the drought?
A scientist in the mid-1990s thinks he's figured it out.
MICHELE: So in 1996, David Johnson,
who is an American scientist,
traveled down to this region and he is the first
to really recognize these large,
almost well-like structures
in the desert, that we call puquios.
FORREST: The puquios are the spiral-shaped
stone staircases around a hole
that leads underground to stone-reinforced tunnels
under the earth, lined with waterproof clay.
MICHAEL: The locals really talk about these
as connected to an irrigation system,
a way of getting water to flow throughout the area.
One of the interesting things is how old they are.
They date back at least to the 6th century
and they're really connected with the ending
of this massive drought that decimated the area.
FORREST: Johnson realizes there's a connection
between the Nazca Lines and these puquios,
and starts working on a theory of his own.
He believes, after the drought, the Nazca people repurposed
their famous Lines and created a map for one
of the world's most sophisticated systems
of water management.
♪ ♪
LAURENCE: Johnson finds two underground water sources
in the Nazca desert to support his theory.
The first are rivers, which flow down
from the mountains before going underground through this region.
The second are geological fault lines that run
north to south that bring up their own water
from deeper beneath the water table.
When you look at this area,
not only is it one of the driest,
it's also one of the most seismically active areas,
and so there's actually a lot of fault lines in this region.
FORREST: Johnson notices lots of this area's ancient settlements
are located right next to faults and that there's
usually a puquio system there, in that spot, to tap
into its water source, and right on top of the faults,
in almost every case, he finds there are
Nazca Lines marking their paths.
The geometric shapes were designed to track and locate
underground water sources.
So, in this process, it's a way for the Nazca people
to take control of the water,
instead of just leaving it up to chance,
as to whether or not rain or runoff will show up.
These puquios ensure a reliable supply of water year-round,
meaning they're able to turn this arid desert
into arable farmland strictly through their own ingenuity.
LAURENCE: This method is not just relegated to antiquity.
Johnson is impressed the locals are
still using the system the Nazca created
some 1,500 years later.
There are around 30 of these puquios
still in use in the Nazca Valley.
But it really takes a lot of constant repair and work.
So many are falling apart and, you know, are out of use,
but they are still usable
where they've been taken care of.
LAURENCE: Johnson shares his insight
with archeologist Donald Proulx
and hydrologist Stephen Mabee.
FORREST: From 1996 to 2000,
they form the Nazca Lines Project,
plotting the course of several faults to look
for correlations with the Lines,
and they're able to confirm Johnson's ideas.
In almost every case they study, they find Nazca Lines
charting the path of the faults
and pointing to where the faults cross adjacent ridges.
As they finished it, they really came away feeling like they had
solved one of archeology's greatest mysteries.
If this theory is correct, the Nazcans have created a map
of the underground water sources,
which they can now tap into to survive.
It's like your local water utility map
on a one to one scale.
This is a complex but effective way of recording
knowledge onto the earth for later generations to use.
LAURENCE: But what about the animal shapes?
CAROLINE: This is why we think the Nazca Lines
may have been repurposed.
The animal shapes began as symbolic prayers
or offerings to bring rainfall.
LAURENCE: According to Johnson, they eventually become part
of the system as well.
While the most important mapping of the irrigation system
is done with geometric shapes,
Johnson writes that the animal figures
might have been used to name the different water sources
or indicate where they change direction.
CAROLINE: These puquios are an incredible achievement,
and the Nazca Lines are a huge part
of what makes them function as a system.
People still thrive in a desert area
because of the knowledge they receive from the Lines.
A map for survival written in the sands.
♪ ♪
LAURENCE: Over the last century,
the world has marveled
at the many impressive achievements
of the Nazca people.
The Lines themselves are incredible,
but we can't forget about all of the other interesting
artifacts and features that have been found in this region.
There are some of the world's finest textiles
with incredibly elaborate designs.
There's beautifully made pottery.
MICHELE: There are hundreds of mummies that are
way better preserved than what we even see in ancient Egypt.
FORREST: And there's a centuries-old
underground water management system that works so well,
it's still in use today.
♪ ♪
LAURENCE: But there's also
a much more disturbing discovery.
MICHAEL: About 90 years ago, Alfred Lewis Kroeber,
an anthropologist, was studying in the area,
and what he found was a collection of severed heads.
MICHELE: So these heads are really well-preserved,
much like the mummies that we find
in this region, because of the lack of rain,
but what's interesting about them is that they have
holes in the center of their forehead.
And what we think these holes were for
is to put a string so that the head could be carried.
FORREST: Experts have long believed that these are
trophy heads, taken from rivals during war,
and then carried around and put on display.
Some heads are even found next to full mummies,
and researchers believe that a person might be buried
along with the trophy heads they collected in life.
LAURENCE: For nearly a century,
these heads are thought to belong
to enemies of the Nazca.
MICHELE: But years later, a team of scientists, in 2009
undertook some studies on these trophy heads
by using strontium analysis,
which can tell you where a person
was originally born, how that water in the ground was
incorporated into their bones and into their teeth.
They were able to tell where these heads originated.
Come to find out, the severed trophy heads
come from other Nazcans.
♪ ♪
LAURENCE: The finding leads some archeologists
to completely rethink the Nazca Lines.
We have a feeling the Lines are linked to rituals
or spirituality somehow, and we have a feeling
they are linked to the precious resource of water.
This new theory takes all of that into account,
plus the fact that we now have evidence
of local natives being beheaded.
MICHAEL: What does this mean? Well, according to archeologists
Donald Proulx and Corina Kellner,
what you have is a situation where the Nazca Lines
could be connected to ritual human sacrifice.
♪ ♪
FORREST: If you examine the images
on pottery and textiles from the Nazca,
trophy heads are everywhere.
Sometimes they're shown with plants sprouting
from them, which indicate they were likely buried
to increase agricultural fertility.
As we know now, these are local Nazcans.
They're not people from other areas,
so they presumably were not taken in war or battle.
These are people who have freely participated in the process
and in the ritual to help their own community.
LAURENCE: According to this theory,
the venue for these rituals is the Nazca Lines.
When we look at the geometric figures,
we realize there are these giant open spaces,
and these are potentially the arenas
for these ritual sacrifices,
whether they were battles that were played out
or other ritual actions.
In the Andean culture, warfare is actually linked to fertility,
and the losers of battle are sacrificed to the gods
to help with that fertility.
FORREST: This is all part of a religious attempt
to draw in water.
As the team dates the trophy heads,
they feel more confident about this theory,
because, right when the major drought hits the region
the number of trophy heads increases dramatically.
They start doing this ritual more and more in desperation.
LAURENCE: In 2022, a Polish research team finds
further proof to support this theory.
FORREST: This team tests hair samples
from the Nazca trophy heads
and finds that, before their deaths,
the victims ingested San Pedro cactus,
which contains mescaline.
MICHAEL: Right before the victims were killed
or sacrificed, as part of the ritual,
they were given this hallucinogen to prepare them.
FORREST: You find images of the San Pedro cactus
everywhere in Nazca iconography.
FORREST: This plant is clearly important to their religion,
and now we have proof that it's involved
in their rituals of taking trophy heads.
MICHAEL: The idea is that the Nazca would gather
at the Lines in these ritual spaces.
They would participate in the rituals,
ingest the hallucinogenic drug.
This would put them in a trance-like state
and prepare them to engage in the ritual battle.
At the end of the battle, the trophy heads would then be
buried with the hopes of inspiring
the gods to bring water to the area.
LAURENCE: But this is far from the final word
on the Nazca Lines.
FORREST: Maybe the Lines were ritual battlefields,
but I don't think that's all they ever were.
There's a good chance they serve multiple functions.
It's like roads today.
Yes, they move people from one place to another,
but we also stage parades down them.
We block them off for music festivals.
We bury our water pipes beneath them.
This seems like a more logical way to view the Nazca Lines.
MICHAEL: Are we ever really going to know
what the Lines were used for?
Probably not, and that's okay.
That's what's exciting about them.
But one thing we definitely know
is the amazing feat of engineering
that these Lines represent.
They were clearly very, very important
to the people of the time.
They cared deeply about them,
went to great lengths to build them,
and it is a real testament to human ingenuity, creativity,
and ability to build amazing things.
Despite their 2,000 year-old history,
more Nazca Lines are still being discovered.
A never before seen cat figure was found as recently as 2020.
Perhaps new evidence can finally reveal their true purpose.
I'm Laurence Fishburne.
Thank you for watching "History's Greatest Mysteries."
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