The Stone at the Centre Lost Kingdoms of South America

High in the Bolivian Andes

stand the awe-inspiring ruins of a massive temple city.

This is Tiwanaku, which means "the stone at the centre of the world".

Over 1,000 years ago in this sacred site,

ritual drinking and feasting

fuelled the most powerful religion that South America had ever seen.

I'm Jago Cooper

and, as an archaeologist who specialises in South America,

I've always been fascinated by the secrets and mysteries

buried deep in these awe-inspiring and forbidding landscapes.

The history of this continent has been dominated

by the stories of the Inca and the Spanish conquistadors.

'But in this series,

'I'll be exploring an older, forgotten past...'

Wow! We're inside the cave.

'..travelling from the coast to the clouds

'in search of ancient civilisations

'as significant and impressive as anywhere else on Earth.'

Here in Bolivia, the monolithic temple city of Tiwanaku

stands at the breathtaking height of 13,000 feet above sea level.

But Tiwanaku wasn't just a place, it was a people,

who created a civilisation that lasted over 500 years.

For centuries, it was a mystery how the Tiwanaku people

managed to thrive in this desolate landscape.

But now, archaeology has revealed

evidence of astonishing community effort...

..of a deep understanding of the environment...

MEN CHANT

..and, amazingly, how a crucial role in Tiwanaku's dominance

was played by beer.

Up here in these remote, high plains of Bolivia,

I want to find out the truth behind the stories of the Tiwanaku people.

How did their beliefs give them the power and ability

to build a city of temples in this hostile and unforgiving land?

The Altiplano, the high plain,

forms a vast expanse 3,800 metres up in the Bolivian Andes...

..part of the vast mountain range

that forms a spine down western South America.

Life's hard up here.

The air's thin, it's difficult to breathe.

Although daytime temperatures go over 20 degrees,

at night, it drops well below freezing.

The rainy season brings floods

and, periodically, the area suffers catastrophic drought.

To European eyes, this seems like

the last place on Earth that humans would settle.

Yet between around 600 and 1100 AD, a civilisation grew

that eventually numbered a million people.

This was the heartland of the Tiwanaku,

and their influence stretched from here

as far as Peru, Chile and Argentina.

So what made life on one of the world's

highest plateau regions possible? How did the Tiwanaku

survive the thin air and temperature extremes up here?

And how on earth did they travel any distance across this landscape?

This is a country that,

until the arrival of the Europeans in the 16th century,

they saw no need for the use of the wheel

and, driving around, you can see why.

It's a really inhospitable terrain

and it's much better to walk across it than to try and drive.

But the Altiplano offers a different form of transport

that people in this region began exploiting at least 6,000 years ago

and I've come to the remote community of San Antonio Murce,

where they still depend on it.

There's one thing that makes this community viable,

and it's the same thing

that makes the communities in early Tiwanaku viable.

And that's the animal unique to South America - the llama.

THEY GREET EACH OTHER IN SPANISH

'This is Marcelo Choqui. His family have lived here,

'surviving as llama herders, for generations.

'They are Aymara,

'an indigenous Bolivian group descended from the Tiwanaku people

'from whom we can learn a lot about how their ancestors lived.'

CONVERSATION IN SPANISH CONTINUES

'In common with many South American cultures,

'it's the custom here to share coca leaves when you first meet.

'But here on the Altiplano,

'coca is also used to cope with the thin air you get at this altitude.'

'So coca gave the Tiwanaku

'the stamina to work at this airless height,

'and the llama provided them with wool for the kind of clothing

'needed to battle the temperature extremes up here.

'Marcelo's daughter weaves it into vivid textiles.'

The llama wool is so important for the communities here,

not only cos it gets incredibly cold during the winters,

but also because it was the thing they used for all their clothing.

Here, they're using the same colours for this particular village

that they've been using for hundreds of years.

'But, of course, the llama wasn't just a source of wool and clothing.'

So we're loading up the bags with some fertiliser,

cos Marcelo's getting ready to start planting the crops for the year.

We'll take the fertiliser, pack 'em on the llamas

and take them up to the fields higher up in the mountains.

They're going to use it to plant the potatoes in the fields

and he says that's one of the only crops they can grow up here.

'In this terrain,

'the llama is Marcelo's four-wheel drive and his tractor.'

The llama is uniquely built to travel huge distances

up in these high altitudes over tough terrain.

The problem is, at these high altitudes,

I'm beginning to get a bit out of breath.

'Llama herding was vital

'for the earliest inhabitants of the Altiplano.

'It fed and clothed them, and llama trains,

'sometimes a mile long, would traverse the mountain passes

'carrying goods and supplies between communities.

'Yet, even today, I'm struck by how precarious

'Marcelo and his family's existence seems to be.'

It only takes one frost and he can lose half his crop

and it gives you the sense of how harsh this environment is

and how vulnerable they are,

cos they're only growing enough food for themselves.

'So a llama herd could support the subsistence lifestyle

'that persisted until around 1000 BC.

'But to become a dominant civilisation,

'the Tiwanaku would've needed a far greater food supply.'

To see how they did it, I'm heading to an area of the Altiplano

where the Tiwanaku first began to emerge around 3,000 years ago,

on the shores of an ancient lake.

With a surface area of over 3,200 square miles,

Lake Titicaca is the highest navigable lake in the world.

The region around the lake is known as the Titicaca Basin

and archaeologists think that it was here, almost 3,000 years ago,

that the Tiwanaku first started out as groups of subsistence farmers.

It's more like an inland sea than a lake, really,

and, for thousands of years, it's played two crucial roles

for the people living along its shores.

The first is that the lake has an ambient temperature

which doesn't move around a lot, and that really helps create

a microclimate of stability along these lake shores.

And the second is that the sedimentation of the lake

has created this really rich agricultural soil

that you can see being used today.

You can just see how rich they are.

But compare this with the soils from higher up in the valley,

you can see it just runs through the hands.

So this is where the Tiwanaku started their subsistence life.

But this high up, crops grown any distance from the local microclimate

would've been vulnerable to frost or drought, limiting expansion.

For the civilisation to grow,

they had to find a way to cultivate land outside the lake's protection.

And a little further inland,

we can find the relics that explain how they did it.

The early Tiwanaku didn't adapt to their landscape, they transformed it

and, here at the site of Koani Pampa, you can see how.

The Koani Pampa is a vast stretch of the Altiplano

leading up from Lake Titicaca

and these are the visible remains of ancient, ingenious engineering.

These raised beds were an agricultural innovation

that transformed the agricultural production in the region.

They're really clever, because the water acted as a buffer to protect

the crops in the raised beds against the harsh frosts you get here.

Meltwater coming down from the snow and glaciers on the mountains

irrigated the fields.

The water in these trenches retained the heat of the daytime sun,

creating a mini-microclimate, just like the lake,

which protected the crops.

But it's the investment

in maintaining these raised beds every year that is key.

They would straighten up these edges,

which allows the water to be absorbed.

They would dig out the channels

with the nutrient-rich soil they'd put on top of the bed

and then they'd turn it all over

to allow a huge increase in agricultural production.

Modern experiments have shown that using this method

could've given the Tiwanaku 25% more crops,

extending their growing season by two valuable weeks.

They didn't have any draught animals or ploughs,

so all of this would've been done with hand tools.

The sheer amount of labour

going into building and maintaining these raised fields is mind-boggling

and this is just a fraction of the landscape

that was exploited in this way.

This kind of farming was incredibly labour intensive,

and could only have worked

if the small Tiwanaku communities around the lake

managed to come together in a collective effort.

Something must have motivated them to do this

rather than simply look after their individual interests.

The key to understanding what that was lies back at the lake.

Scattered around Lake Titicaca's shores, archaeologists have

discovered the remains of numerous Tiwanaku temples

and these hold the key.

Archaeological research suggests that the Tiwanaku religion

was devoted to group worship of gods of nature

that controlled the environment and granted good harvests.

I've come to see one of the oldest temple sites,

where the Tiwanaku were holding religious festivals 3,000 years ago.

This is the sunken court of Chirpa.

You can really get a sense of the atmosphere

that can be created during the festivals.

People would be standing up here, around the court,

all looking down, focused on the festival inside.

In an echo of the ancient practices of their Tiwanaku ancestors,

the local Aymara still use this site to perform ritual llama sacrifices,

offering the blood to the stones as part of their annual festivals.

The festivals here not only served to bring together

the Tiwanaku communities to appease the gods with ritual offerings,

but they also bound them together socially.

As they celebrated and prayed, they must've formed an ideology

that suggested not just worshipping together

but working together was the key to success.

Coming to a site like this,

you can really see the foundations of what Tiwanaku was all about,

but what I want to find out is how the Tiwanaku

went from a small site like this one at a community scale

to the monumental architecture of Tiwanaku at the regional scale.

A present-day Aymara festival can demonstrate how ritual gatherings

helped Tiwanaku civilisation evolve into a more centralised state.

MUSIC PLAYS

I've come to experience a festival

that attracts thousands from the surrounding valleys

to a tiny village called Cala.

MUSIC CONTINUES

Cala only has a population of 250 people,

but today, it's going to swell to 4,000 people

ready to drink, dance and party Bolivian-style.

I'm here in Bolivia near the start of spring,

just when the local communities start planting crops.

Here we see how festivals and working communities can be linked.

Anthropologist Carlos Candora is an expert

in the religious traditions and rituals of the Altiplano.

From up here, you get a great view of people

flocking into this festival. There's people arriving in buses,

there's llama trains coming over the hills,

there's people walking through these desert landscapes. This place

acts like a magnet, bringing people together from all over the region.

Nowadays, the dominant faith in Bolivia is Catholicism

and the official focus of this festival is the church,

where there are prayers, ritual offerings and blessings.

But whilst the church is part of it, there's much more to it.

Here in the solemnity of the church,

people are making their offerings and preparing for the year.

And outside, people are going pretty crazy and drinking a lot of beer.

People have come together to worship, yes,

but, as the Tiwanaku did, they're gathering en masse,

coming together as a community to party, forming the bonds

that will see them through the tough agricultural season to come.

The bigger the party, the better the growing season will be.

Over eight centuries, the Tiwanaku gatherings got bigger and bigger

and the collective labour force grew in the process,

getting closer and closer to mastering their harsh environment.

And around 200 BC, they began building a temple complex to hold

the biggest religious festivals that South America had ever seen.

Situated ten miles from the shores of Lake Titicaca, in Aymara,

Tiwanaku means "stone at the centre".

And this extraordinary place

became the focal point of the entire civilisation.

The oldest part of it is this -

the sunken temple lined with the carved heads of Tiwanaku ancestors.

Tiwanaku began with the construction of this early sunken court.

Like the many sunken courts throughout the Titicaca Basin,

it was a community-focused ritual space, but over the next 800 years,

Tiwanaku just grew bigger and bigger and bigger.

Adjoining the sunken temple is the Kalasasaya,

a raised ceremonial space measuring over 15,000 square metres

that the Tiwanaku began building in 500 AD.

A monolithic statue guards the entrance way

and in one corner of it stands this - the Sun Gate -

shaped from a single slab of stone.

The character carved on it is known as the Staff God,

a controller of natural forces,

of the sun, the rain and seasonal chance.

1,500 years ago, this was the place where tens of thousands of people

gathered to pay homage to the gods of nature.

And, just like their modern counterparts,

Tiwanaku communities from across the region

came together to reaffirm their social bonds

and mobilise themselves into massive work parties

in readiness for the new agricultural year.

Dominating the site is a large mound

once encased in massive masonry blocks, long since eroded or looted.

It's only from up here that you get a sense of the scale of the place.

Only a fraction of this site has actually been excavated

and archaeologists estimate that the footprint is

well over five square kilometres.

The question that puzzled archaeologists for decades is

how was Tiwanaku built?

Attempts were made in the 1960s

to rebuild some of the temple structures, a process that revealed

how phenomenally skilled at stoneworking the Tiwanaku were.

And quite apart from their skill,

how did a culture that had no horse or oxen for dragging,

that didn't use the wheel or the pulley,

move stones that weighed 10, 20 or even 50 tonnes,

stones that were quarried miles away?

To find out, I have to go back

to where the stones came from - Lake Titicaca -

where there is a clue to the mystery of Tiwanaku's construction.

Many of the monolithic stones at Tiwanaku

are of a very specific type of volcanic rock

that archaeologists have identified as having been quarried

on a peninsula 25 miles away across the lake.

And on the lake shore lie dozens of seemingly abandoned stones

that could only have come from the peninsula quarry.

'The local Aymara call them the "piedras cansadas" -

'the tired stones.'

There's one over there.

'And they seem to have been left here,

'halfway between the quarry and Tiwanaku.'

Talk about seeing archaeology abandoned in the landscape.

There's a stone in the middle of a ploughed field.

There's another one just up there

and they're forming a line to the edge of the lake.

This is a truly impressive piece of stone.

It's a green andesite, which is completely different

to the softer sandstones you get in this part of the Titicaca Basin.

If you look at the edges, you can see how it's been worked,

faced off into a nice rectangular block.

You can see where the rock's been cut,

cut marks facing it down with these vertical sides.

There's a notch in here.

There's some more cut marks showing a notch down there.

And some more over here.

Seeing how they've started to shape this stone into an initial form

gives us an idea of what it was going to be used for,

one of the massive stone lintels

or part of the major structures of the big temples we get at Tiwanaku.

So how were these colossal stones transported here

from a quarry 25 miles across the lake?

The obvious conclusion is that they were shipped across

and unloaded here en route to Tiwanaku.

But this is a virtually treeless landscape,

so they couldn't have been brought here by boat.

Not wooden ones, anyway.

The lake offers a different resource that can be used for boat building.

Totora reeds.

'I'm meeting with Professor Alexei Vranich,

'an archaeologist who is one of the world's leading experts on Tiwanaku.

'He's brought me to see a traditional boat-building technique

'using totora reeds harvested from the lake.'

THEY GREET EACH OTHER IN SPANISH

So he's making these two right now.

Well, actually, this is just going to be one boat.

-So he has the two parts of it.

-Yeah.

-And then, the heart is going to be in the middle.

-Yeah.

'It's a centuries-old skill and it's boats like these

'that Alexei believes the Tiwanaku used to transport their stones.'

We know that the Andean people were very practical,

knew their environment and knew how to use the natural resources.

And there's this long tradition of building these boats.

Now they're small, but we read about

and even saw old drawings of much larger boats.

Now, this is one man making one boat.

Imagine if the entire community, they said,

"OK, everyone has to make one boat," and you tie together 50 boats.

That's a huge raft that literally one person with a rope

could drag all along the coastline.

So, literally, they're doing industrial-sized moving of stones,

but using pretty much a home technology.

'The reeds themselves aren't just hollow tubes.

'Inside is a fibrous membrane that makes them extremely strong.

'The bindings are retightened

'several times throughout the construction process

'and the end result is virtually unsinkable.'

'To give me an idea of just how sturdy the totora reed boats are,

'I get to test-drive one on the lake.'

'Clearly for the Tiwanaku,

'boats like this let them use Lake Titicaca like a superhighway,

'a method of transporting themselves across great distances

'with far greater ease than struggling across the mountains.'

I'm 16½ stone and, standing on this thing, it feels solid as a rock.

You can just imagine how these things were being used

to transport people, families, goods around Lake Titicaca,

connecting the Tiwanaku community together.

But could a reed boat like this, even a much bigger one,

really have been capable of carrying a ten-tonne stone

of the type being used at Tiwanaku?

In 2002, Alexei devised an experiment to prove this theory.

He commissioned a lake-side community

to build a 15-metre-long totora reed boat.

He then sourced a nine-tonne block of green andesite

at the volcanic rock quarry.

With the help of another local community near the quarry,

they loaded the stone onto the reed boat and then sailed it

50 miles around the coastline of the lake to the Tiwanaku side,

bringing it up to the township of Santa Rosa,

where dozens of townsfolk came to meet them.

We pulled up, it was pretty much around here,

and once we had all the people laying around over here,

we said, "We've got to pull this off."

'50 people - men, women and children -

'rolled the stone off the boat

'and moved it 60 metres in less than an hour,

'with no organisation from Alexei's team,

'where it still lies today.'

This is the stone over here that we brought over from the other side.

-Looking pretty sizable.

-It's, er, it's about nine tonnes.

-Yeah?

'This extraordinary experiment certainly gives me an insight

'into how the stones might've been moved across the lake.

'But how were they taken across land to Tiwanaku?'

On the bottom, they're worn and they have little striations,

so they were dragged, so that you grab yourselves some ropes

and you start dragging and dragging. We thought, "How about rollers?"

So we built the rollers, we put it there,

we dragged the rock, smashed all the rollers.

So we said, "That's the great part of experimental archaeology,"

is that you know right away ideas that don't work,

so they would've dragged this and dragged it.

'But how were people organised and motivated into moving these stones?'

When we were trying to move this stone, we came up here

and, just like closed-minded Westerners,

like, "We're going to pay you this money, you do this, you do this,"

we couldn't get anything done at all.

But as soon as one community knew

that the other one was moving the stone, it became competitive.

Once it got competitive between communities,

things went very quickly.

So I could imagine, at Tiwanaku, also being this friendly competition

between different groups, going, "I'm going to build here,

"I'm going to bring this, we're going to have a festival,"

and then, that dynamic continuing for literally centuries.

I love this idea of the festival about moving it,

it takes it beyond any sense of practicality,

and it's much more about the social relationships.

And, for me, it means that, when that community went to Tiwanaku

and they saw the stone that they'd taken through their community,

-it's a statement of their involvement in the site.

-Mm-hm.

It's not a monument that someone else creates, like a palace.

"That's so-and-so's palace." My thought would be like

this is part of our... this is part of our identity.

'So Alexei's experiment seems to demonstrate

'that the collective labour that was so important for farming

'was also used to build ever larger temples.'

'It's a kind of virtuous circle.

'Coming together, communities could built temples.

'And as the social bonds increased the size of the communities,

'they could build bigger ones.'

Tiwanaku was clearly a massive festival site,

but recent studies carried out by Alexei and his team

have revealed that it also had another use.

The grand Kalasasaya temple wasn't just an auditorium,

but was also built to measure the movement of the sun...

..that it worked as a giant calendar.

The buildings, actually the entire site,

is designed along astronomical lines.

Sun, moon, stars.

In this case, for the Kalasasaya, the sun is very important.

Now if we turn this way,

we're standing right now on the platform, where I would imagine

one or two or three important people would stand.

The sun would travel across,

and right along there, that's the horizon.

Now the pillar in the middle,

that's where the sun's going to land for the equinox sunset.

On each side is the solstice and in the middle are several others that we

argue about a lot, but there's a good chance that the Tiwanaku

had their own ritual calendar and they had to keep dates based on ideas

of their cosmos and certain offerings being done at different times.

So, we have this idea that not only is it a calendar of agriculture,

it's a calendar of festivals as well.

For sure, they had something going here, saying now it's time

for this festival, now it's time for this offering.

The Kalasasaya worked as an astronomical state clock

that regulated the Tiwanaku's worship

and agricultural operations on a regional scale.

The Kalasasaya defined their culture of collective effort

and the rituals carried out there were designed to be intense,

theatrical events.

If we were standing here, 500 AD, at one of these solstice festivals,

what would it look like, what would we be seeing?

We see such a pale representation of what it used to be.

Remember that these people would have been wearing bright clothes.

These stones would have been covered in perhaps paint -

greens, reds, blues, really gaudy colours

that to us, make no sense,

but realise that a lot of these people probably would have been

taking ritual intoxicants

and when you take that, those colours move.

So these statues that you see

would actually be moving in their minds and talking to them.

You would have had bright metals, with the sun coming off it.

The Tiwanaku made their metal,

so they could do different types of reflections.

So reflections, gaudy colours, people in very bright clothing,

and then add intoxicants to that.

So thinking about what these people are taking...

they're drinking, they're smoking, there's tobacco,

there's drugs from the Amazon...

what sort of drugs are they taking?

They're taking a couple of hallucinogens.

When we go take a look at some of the monoliths,

you'll see the plants actually carved in there,

where they have these hallucinogens,

and it would have been ground up either as snuff,

perhaps you could drink them.

They also had hallucinogenic enema tubes,

in case you're in a big hurry to get the party started.

And what a party it must have been.

Evidence of the celebrations

that went on here over 1,000 years ago are regularly discovered,

in particular, these beer-drinking vessels called keros.

This sort of thing is typical of the site

and gives us a real sense of the

scale of the site, cos this excavation is about

a kilometre from the centre.

And the significance of beer and intoxicants

to Tiwanaku's rituals and ceremonies

can be found carved into its monolithic figures.

I like this monolithic statue,

looking out into the sacred space of the Kalasasaya.

He's got a beer cup in one hand

and a snuff pipe for taking intoxicant drugs in the other,

and you can just imagine the hundreds of thousands of people

lining this plaza to witness the theatrical, colourful rituals

and offerings to the gods.

Centre stage at these spectacular ceremonies

stood an elite caste of priests.

Wearing iconic robes and headdresses,

they performed the rituals and read the movement of the sun.

The priests interpreted the cosmos for the Tiwanaku people,

telling them when and how they could appease it

and bend it to their will.

How much power they wielded is unknown,

but what at first might seem like a utopian farmer state

is beginning to reveal a darker side.

In 2005, in a grave site sitting in direct line

with the setting of the winter solstice sun,

archaeologists unearthed something at Tiwanaku

that had never been found here before.

When was the last time you were in here?

2006.

'This is one of the artefact storage facilities here at Tiwanaku

'and I'm the first person not with the original excavation team

'to explore its contents.'

What we're looking for are these guys over here.

Let's take a look.

And...oh, we've got a nice skull here.

That's a young one and the molars are coming in.

There's the wisdom teeth.

He's been smacked in the back of the head.

He got smacked in the back of the head.

'This is the first evidence of human sacrifice

'having been practised here at Tiwanaku

'that has ever been uncovered.'

Human sacrifice is not something

I've previously associated with Tiwanaku.

Why do you think sacrifices would have been occurring at Tiwanaku?

These sacrifices...

this is the only one we've found so far.

20 years from now, we might find 100 more,

but this was on the solstice

and the other indicators of the other artefacts here

are associated with the start of the agricultural season,

the start with the rainy season.

It could have been a period of like...it's very important that we

get some rain to grow some potatoes and to grow some other things.

So, this year's solstice celebration

is going to contain a couple of special guests!

This sacrifice suggests

that the Tiwanaku had become increasingly dependent

on good harvests to maintain their civilisation's momentum.

And 200 years after the Kalasasaya temple was complete,

construction began on what was then

the largest structure in the Andes -

the Akapana Pyramid.

The Akapana is a completely man-made hill,

but 1,000 years of erosion and looting

has reduced it to a shapeless mound.

Recent attempts have been made to reconstruct a section

of the stepped sides that once went all the way to its 17-metre summit.

You can imagine that it would be quite

an exclusive spot for a privileged elite to stand here

overlooking the rituals and ceremonies

taking place in the Kalasasaya.

But if this was Ancient Egypt, it'd be a Pharaoh stood up here,

but crucially, Tiwanaku doesn't have any Pharaohs,

or kings.

There is absolutely no evidence of a king at Tiwanaku,

no monuments dedicated to a single autocratic ruler.

Instead, archaeologists believe that the Akapana is a monument to

the mountains, the snow from which melted each spring

and irrigated Tiwanaku's huge agricultural systems.

What ruled the Tiwanaku was their ideology of nature worship

and their cult of collectivism.

Here at their temple city, the stone at the centre,

they had come together and mastered their harsh environment.

To get a picture of Tiwanaku civilisation at its height,

I've come to La Paz.

Nestled in the mountains on the eastern edge of the Altiplano

and sitting at 3,600 metres,

La Paz is the world's highest capital city.

Its museum houses a collection of Tiwanaku artefacts

that give us a glimpse of what it would have been like

to witness one of their festivals.

THEY EXCHANGE GREETINGS

I'm being shown around by archaeologist Marcos Michel,

and one thing immediately catches my eye -

a Tiwanaku skull.

It is a skull that has been deliberately deformed,

so that the back of it is elongated.

It was a practice carried out

to identify this person as one of the Tiwanaku.

These sorts of things were done as a form of beauty...

And, of course, there are the beer cups.

Highly decorated vessels like these

were used for ceremonial beer drinking that, as we've seen,

were at the heart of Tiwanaku's festivals.

But a rarer object on display here is this fantastic textile.

The Tiwanaku left no written history,

but that's not to say that they weren't recording stories.

If you look at this tapestry,

there are certain symbols which are repeated over and over again.

And there is a narrative here,

explaining to people who understand those symbols what's going on.

To my mind, it's something like the Bayeux Tapestry,

an idea that you can understand a storyline.

But unlike the Bayeux Tapestry,

sadly no-one yet knows how to fully interpret these symbols

or their meaning.

One thing we do know, though, is that by 700 AD

the Tiwanaku began spreading far beyond the communities

living around Lake Titicaca.

Leading their llama trains down off the Altiplano,

they moved into warmer climate zones

as far afield as Chile and Peru,

hundreds of miles away from their heartland.

Yet surprisingly, this expansion doesn't seem to have been one

of conquest or empire building.

To discover how and why they came to influence

such a vast area of South America,

I'm going to travel to the far eastern frontier

of Tiwanaku territory,

250 miles away from the Titicaca Basin

and 1,500 metres lower.

Lying at 2,250 metres above sea level,

this is the modern-day city of Cochabamba

and the Tiwanaku began arriving in these valleys when it was

nothing more than a collection of farming communities around 750 AD.

Imagine what it would have been like to see the Tiwanaku

coming down out of the mountains, with their colourful textiles,

elongated heads and mile-long llama trains.

Blessed with an eternal spring climate,

the Cochabamba Valley is a fantastically rich

agricultural region.

On the Altiplano,

the Tiwanaku struggled to grow anything other

than high-altitude grains and potatoes in any quantity,

but down here they could produce an abundance of one crop,

which we've seen was vital to the functioning of their civilisation.

The Tiwanaku came to this valley

because of its fantastic capacity to grow this - maize.

And they wanted maize to make beer. Lots and lots of beer.

HE SPEAKS SPANISH

'This is a brewery that makes Chicha,

'a strong maize beer that's been made in this region for centuries.'

Beer drinking was an integral part of Tiwanaku's festivals.

As those festivals became bigger and more spectacular,

they needed beer in ever greater quantities.

The search for maize to make more beer

was one of the main driving forces

of Tiwanaku expansion into the Cochabamba Valley.

Yeah, it's a bit hoochie, but it's quite tasty.

'So, exactly how did this happen?'

How did the Tiwanaku gain control of this region's resources?

30 years ago, it was thought a Tiwanaku army

swept down off the mountains like an imperial power,

to take over and colonise this resource-rich, warmer climate.

It's only now that archaeologists are beginning

to present a completely different picture

of how the Tiwanaku expanded.

In 1985, a new suburban building project

began on the outskirts of Cochabamba.

As the diggers moved in and began churning up what was thought

to be a small mound, they started uncovering bones.

When the builders pulled out a human skull, everything stopped

and the archaeologists were called in.

This may seem like the last place you'd ever expect to find

the remains of an ancient civilisation, but sometimes

the most extraordinary discoveries

turn up in the most unlikely of places.

DOGS BARK

This is the archaeological site of Pinami...

..the remains of a long-forgotten settlement,

offering a glimpse of life here 1,300 years ago.

And I'm going to be shown around

by lead archaeologist Dr Karen Anderson.

-Karen, how are you doing?

-Good to meet you.

-So this is the site of Pinami?

-Yes.

So what does this site reveal about Tiwanaku expansion?

We don't see any evidence of coercion in the way it was adopted.

People look like they were adopting their rituals, their ideology,

their way of life and also their food.

I mean, they're producing more maize, they had more llamas than before,

so they were getting tied into the Tiwanaku state.

So the site tells us that the people who were living here

wanted the Tiwanaku influence, they accepted that on their own terms.

Right, right.

This site is not, as it first appears to be,

a series of old walls.

In fact, it's a mound that has been built up

over several centuries of continual occupation.

Archaeologists have dug down into the mound

to reveal layers of evidence, generation building upon generation.

Well, the earliest date that we have

which is down here is probably in the 700-750 AD range

and the latest date, which is right before the end of Tiwanaku

is about 1100 AD.

So, a good 400 years of occupation,

-or the story of Tiwanaku through 400 years.

-Right.

And it's the items excavated in that time period,

corresponding to the Tiwanaku arrival in the Cochabamba Valley,

that paints a picture of how they made a lasting impact.

People weren't just building houses here,

they were burying their dead.

The excavated skulls show the distinct Tiwanaku style

of cranial modification.

The practice was being adopted by the local population.

Cranial deformation is a really clear ethnic marker.

Once your head is a certain way, you can't disguise it very well.

Talk me through this process of cranial modification.

-It's a real commitment to change the shape of your skull.

-Right.

It would start very early with babies,

when their skulls are soft.

This one is flattened in the front and back.

You would have boards like this and then wrapped around.

This one you would have it, probably, wrapped around.

So, it tends to make a more pointy cone-head look.

However, what they have found here in really significant quantities

is the distinctive Tiwanaku beer-drinking keros.

But tellingly, this wasn't imported from Tiwanaku, it was made locally.

This one is clearly on the outside done in the Tiwanaku style,

it has the Tiwanaku iconography.

On the inside, this is more of a local style.

So, it's a local vessel form with a Tiwanaku

style on the outside,

so we're seeing a real mixing of cultures here,

-with Tiwanaku coming in and local people adopting it.

-Right, right.

Although archaeologists don't know what this iconography means,

we know it's distinct to Tiwanaku.

So, it seems that the keros played a key role in bringing

the locals into Tiwanaku society.

Just as smaller Tiwanaku communities were brought together

at Lake Titicaca,

now other communities effectively joined the party.

The Tiwanaku empire spread, not at the head of an army,

but through the ritualised sharing of beer.

This is a Chicheria -

a family pub that serves the Chicha beer

that was so much a part of Tiwanaku identity

and economy over 1,000 years ago.

A real theme I'm getting from Tiwanaku society

is this idea of sharing labour, of communal projects.

And a part of that is building reciprocal relationships

and Chicha seems to have played a really important role in that.

It was a way to bring people together,

to express reciprocity,

to express communal understanding.

So you're meeting with people, you're doing politics with people,

there's consensus building with people,

and you're also symbolising by how you serve

and with what icons are on it,

some of your allegiances and your ideology,

so it's a way of sharing an allegiance

and also promoting it at the same time.

I see, in, like, some bizarre way,

some parallels with English drinking tea, you know, high tea,

and the paraphernalia associated with tea,

but it's a wider thing about a cultural context,

and you're saying by having this Chicha,

-they also have this wider cultural context of shared values.

-Yes.

Yeah, and in some ways that's similar,

because that was something the Tiwanaku brought,

was this whole, kind of, drinking tradition and paraphernalia

and fancy cups that just had to feel the right way

and have the right shape and have the right icons on them,

so it is sharing a larger shared value system

and it was...everybody liked it,

especially the maize Chicha,

so it's like, "We're sharing something good."

By 1000 AD the practices and ideology of the Tiwanaku

had been embraced by millions across the Andes and beyond.

Yet Tiwanaku wasn't a kingdom or an empire -

if anything, it was like a huge extended family,

with an enveloping cult of collectivism at its core

and it worked.

By drawing communities together,

they had generated an abundance and a culture of generosity,

embodied by the Chicha rituals.

Their ceremonies were all dedicated to worshipping

and making offerings to the environment

that provided that abundance.

Yet that environment would eventually turn on them.

I'm going there, to Huayna Potosi,

one of the many snow-capped mountains

that dominate the landscape of Lake Titicaca.

I want to climb up to 5,000 metres, over half the height of Everest,

to find out why the environment the Tiwanaku so relied upon

and revered turned against them.

The Tiwanaku were utterly dependent on agricultural success

to build and maintain their temple city

and bind their vast territory together.

They needed the sun and the rain to work in harmony,

they needed the snows to melt in the spring

and irrigate their vast field networks.

All of their ritual ceremonies and offerings

were focused on ensuring that happened

and for at least 500 years, it seemed to have done exactly that.

Tiwanaku was one of the highest ancient civilisations in the world

and incredibly exposed to the climate variability of this region.

Meltwaters from glaciers like this one

fed the vast agricultural systems

that made the construction of the monumental temple complex possible.

But what happened when the meltwater stopped?

'The glacier I'm walking on right now is dying.'

Sergio, my guide, told me

that this glacier is receding by 15 metres every year,

due to modern climate change.

But climate variability has been going on for millennia.

Ice core samples taken from Andean glaciers like this one

reveal that there was a drought from 1100 AD onwards,

one that carried on for centuries.

Year after year, less and less meltwater

seeped down to Tiwanaku's fields.

Yields dropped, instances of crop failure increased

and no matter what offerings they made or what rituals were performed,

the Tiwanaku's power to appease the environment had left them.

The ceremonial centre of Tiwanaku had failed its people.

The intensive agricultural systems that supported it,

that fuelled this culture of generosity and feasting,

were impossible to maintain. It became an anachronism,

a monument to a time of plenty that was long gone.

By 1100 AD, the great temple city of Tiwanaku had been abandoned.

Statues of gods and ancestors had been defaced and decapitated

and the rest was left to fall into ruin.

But the story of the stone at the centre doesn't end there.

The Tiwanaku people didn't simply vanish

after the collapse of their state,

they returned to their centuries-old existence

of living in scattered village communities.

Another 400 years would pass before the first Europeans

set foot on the Altiplano

and by then Tiwanaku was a ruin.

When the Spanish conquistadors first laid eyes on Tiwanaku,

they were amazed by its scale and antiquity,

yet it didn't stop them looting the site in search of gold

and ripping out the finely worked stones to serve their Christian god.

VOICES CLAMOUR

This is the church in the modern-day town of Tiwanaku.

It was built between 1580 and 1612.

Nearly every piece of stone in the building

was looted from the ancient site of Tiwanaku.

Even these two statues outside,

which are meant to represent St Peter and St Paul,

are Tiwanaku statues.

Bolivia became independent from Spain in 1825

and gradually regained control of its own destiny.

Today, nearly 1,000 years after it was abandoned,

the indigenous Aymara of Bolivia

are reclaiming the ruins of Tiwanaku as their own.

THEY CHANT

It's dawn on the 21st September,

the southern hemisphere's spring equinox,

and here the local Aymara leaders

are preparing an offering to welcome back the new agricultural year.

1,000 years ago,

Tiwanaku's extraordinary ideology of sharing and collective labour,

a set of beliefs that enveloped millions across the Andes,

was embodied here by highly atmospheric rituals and ceremonies.

They wanted to imagine what Tiwanaku was like 1,000 years ago.

This gives us a real sense of atmosphere,

rituals still being carried out here, in the hearts of Tiwanaku.

The official religion of Bolivia might be the Catholicism introduced

by the Spanish conquistadors, but the Aymara living here

at 4,000 metres above sea level

on their beautiful, yet forbidding, Altiplano,

have always retained Tiwanaku's reverence for this environment.

Tiwanaku was a place that celebrated life

and today, it's enjoying a rebirth.

Subtitles by Red Bee Media Ltd