Original subtitles

WILLIAM SHATNER: Magnificent temples, monumental dams...

and lofty spires

that reach out and touch the sky.

Why do we build?

Huh? Is it just because we need roofs over our heads?

Or is there another, even more profound reason

why we create massive stone monuments...

soaring cathedrals...

and towering skyscrapers?

Are we trying to prove something?

Or perhaps even...

play God?

Well...

that is what we'll try and find out.

♪ ♪

SHATNER: Experts working in the Acoustics Research Centre

at the University of Salford,

publish the results of a groundbreaking study

on one of the most iconic

ancient monuments in the world...

Stonehenge.

In their experiment, the scientists constructed

a scale model 1/12 the actual size

of Stonehenge...

used speakers to shoot sound waves throughout the model...

and measured how sounds reverberated

through the miniature structure.

Their conclusion?

The massive blocks of Stonehenge

were designed...

to amplify sound.

ANDREW COLLINS: Everybody knows about Stonehenge.

This is the most famous megalithic monument

anywhere in the world.

But who created this?

Why would they have done it?

What research is now beginning to suggest is that

one of the possibilities is to enhance

the generation of sound used in ritual.

SHATNER: The idea that Stonehenge was used to amplify sounds

made during rituals is intriguing.

But it is just the latest in a long line of theories

about this mysterious structure.

After centuries of study and speculation,

Stonehenge continues to inspire both fascination

and intense debate as to how

and why it was built.

HUGH NEWMAN: Stonehenge is the most magnificent stone circle

in the British Isles.

It's unique, it's unlike any stone circle

anywhere on the planet.

It has lintels above it, it's perfectly circular.

And it really stands out as the kind

of symbol of ancient Britain.

People are kind of obsessed by it because it's the only way

they can get back to have some contact with their ancestors.

SHATNER: Believed to be constructed in 3000 BC,

Stonehenge has stood on the plains of Wiltshire, England

for at least 5,000 years.

With an outer ring of 30 four-ton stones

surrounding five huge arches

whose massive blocks weigh 25 tons each,

Stonehenge's construction

defies explanation.

Such a project could not have been achieved haphazardly.

LYNN PICKNETT: We know that some of the stones

were actually imported from South Wales,

which was something like 120 miles away.

A bit tricky when you don't have

flatbed trucks or decent roads.

NEWMAN: Some of the stones at Stonehenge

weigh between 50 and 70 tons.

So how could you have moved them from Wales

to construct Stonehenge?

These are answers that have not been properly dealt with.

PICKNETT: For part of the journey, it's been worked out

that they would've floated them on boats.

But then there would be quite a bit of land

to drag them across

and presumably they used greased rollers

and an awful lot of manpower.

But, again, we don't know.

Once people have actually got the stones

to the site at Stonehenge,

the next major problem is

how do you lift them up in the air?

And the only way I can think

that you would do that is that you would make

a ramp and you would drag them up the ramp,

and then tip them off the end.

That's a massive undertaking,

so we're talking about thousands of people

involved creating Stonehenge.

And these people are working 150 miles apart.

Just imagine how complex those logistics are.

We may never really know how they did it.

SHATNER: As if transporting, hoisting, and precisely balancing

those giant stones wasn't incredible enough,

scholars have observed that Stonehenge's entrance

aligns perfectly

with the rising sun on the summer solstice.

The longest day of the year.

COLLINS: It was almost like a marriage of heaven and earth together

to get closer to heaven.

And it seemed to be bringing down the influence

of the sky world

on Earth itself.

NEWMAN: It does seem that they wanted to influence

and integrate the natural energies of the Earth.

And these massive megalithic boulders

with cosmic energies from above

to create this enchanted space

where people could have ceremony.

SHATNER: Were Stonehenge's megalithic boulders intended

to be energetically linked to the power of the sun

in some way?

It's certainly a thought-provoking question.

And it might help to explain yet another mystery.

The burial sites that are all around Stonehenge.

You can see hundreds of burial mounds.

The kind of people that are buried there

come from all over Europe.

In other words, they were visitors there.

It was a site that people were coming to

from all over Europe.

Now, why were they coming there?

What's strange is that the archaeology suggests

that many of these people had some long-term illness

or disability, suggesting that they were going to Stonehenge

in the hope of a cure.

SHATNER: Stonehenge, a healing sanctuary?

But why would people struggling with illness

think that this stone circle could cure them?

PHILLIPS: Some of the stones at Stonehenge

are called bluestones.

There's only one place that bluestone

can be got in the British Isles,

and that's the Preseli Hills in South Wales.

We know that they moved those stones

all the way from South Wales to Stonehenge,

but why would they do this?

Why would they need those very specific

kind of stones?

NEWMAN: In ancient traditions of

the Preseli Mountains where the bluestones

of Stonehenge originally came from,

it states that if you poured water over the stones,

and then you drank the water, it would have healing effects.

And the idea was people would come from all over Europe

and actually come to Stonehenge to be healed,

not just using the energy of the stones,

but also the water that was poured

over the stones and then drunk.

SHATNER: Is it possible that the bluestones

that make up Stonehenge

actually have healing properties?

For some, that sounds rather fantastical and hard to believe.

But for others, it's one of the many intriguing theories

that makes Stonehenge

so fascinating.

PHILLIPS: We may never know why they brought the bluestones

from 150 miles away.

We may never know why they built Stonehenge

because they left no writing behind.

But we do know that Stonehenge attracts

over a million visitors every year.

It attracts new-age travelers.

It attracts occultists.

It attracts ordinary, everyday people.

There's something about Stonehenge

that seems to act as a magnet.

SHATNER: Stonehenge is evidence of humanity's desire to build

a structure that was more than just a place of shelter.

It is an early example of a primal urge within us

to create something greater than ourselves.

But what motivates this ambition in the first place?

Well, perhaps a clue can be found a little later in history

by examining the engineering of the ancient Greeks

and the strange perfection

of the Parthenon.

SHATNER: High atop the Acropolis in Athens, Greece

stands one of the most magnificent

and most aesthetically pleasing structures in the world.

The Parthenon.

This 23,000-square-foot temple

was constructed using 100,000 tons of radiant white marble.

The exterior of the Parthenon is lined

with 46 colossal columns...

which strikingly appear to be laid out

in the shape of an exact rectangle.

And what's more astonishing is that the more than

13,000 stone blocks used to assemble the Parthenon

were precisely fitted together,

without the use of mortar.

Which begs the question...

how were the ancient Greeks able

to build something that looks so...

perfect?

JONATHAN YOUNG: The Parthenon is an amazingly beautiful structure.

The design, the spacing of each stone

is so perfect that it inspires just to look at.

The proportions are so exact.

For a large building, it is an amazing thing.

And it lifts the spirit upward.

SHATNER: Built beginning in 447 BC

on the orders of the famed statesman and general Pericles,

the Parthenon celebrates the Athenians' victory

over Persian invaders...

who had tried to conquer the city for 50 years.

DORAN: Athens during the time of the building of the Parthenon

is an incredible, cosmopolitan, vibrant city.

It's producing art, literature,

sculpture, architecture.

It's the Manhattan of the fifth century BC.

And I think if you're an Athenian citizen,

walking, doing your everyday work,

and then you see the Acropolis in the center of the city,

this incredible shining hill,

and then you see the Parthenon-- the gleaming marble,

the biggest and most beautiful Greek temple that existed,

at least in mainland Greece at this point--

you'd be filled with a sense of wonder.

SHATNER: Although most of the interior of the Parthenon has decayed

due to the ravages of time,

the rectangular symmetry of its exterior

looks flawless to this day.

But strangely, for a temple that was clearly built

with perfection in mind,

what makes the Parthenon so fascinating

is actually its imperfections.

Not only were the Greeks masters of geometry,

they were also masters of optical illusions.

They knew the fact that your eye plays tricks on you.

Therefore, they built the Parthenon

"slightly incorrectly," quote, unquote,

to compensate for this

so that the net result is perfection.

DORAN: The Parthenon is a rectangle,

but there are no right angles in the entire building.

Everything is slightly off.

The columns look straight from below,

but they are slightly tilted toward each other.

So if you were standing at the base of the Parthenon,

and if the columns didn't stop after a certain number of feet,

but they kept on going all the way up into the sky,

you would see the columns meeting

if they were long enough to actually meet.

This is a very curious thing that the builders did.

KAKU: It turns out that the Parthenon does not have

straight parallel lines at all.

The columns are not vertically cylindrical at all.

They bulge by about an inch at the center of the cylinder.

So, for example, the human brain, looking at a column,

will actually think that the waist is pinched.

Your eye thinks that the center of the cylinder

is shrunk.

To compensate for that,

the columns of the Parthenon bulge.

There's no way this could have been an accident.

SHATNER: But is that all the Greeks were trying to achieve--

an optical illusion?

Or could they have had another purpose in mind

when they built the Parthenon?

COLLINS: Why do we create monuments like the Parthenon?

And the answer is,

we want to try and imitate the divine.

The divine was seen as perfection.

The gods are seen as perfection.

And so sacred geometry

has been incorporated into the Parthenon

in the belief that it was now endowed

with some kind of divine power.

And this was done very specifically

to connect the mundane with the divine

to create the connection between this world and the next.

SHATNER: Is the unique design of the Parthenon

some kind of attempt to connect to a higher power?

According to some researchers, the answer is yes.

And they claim that the fact that the Parthenon still stands,

and that it still looks perfect and pleasing to the eye,

is a testament to what its architects

were striving to build: something eternal, everlasting

and, perhaps, divine.

Just like another extraordinary structure

that was constructed more than a thousand years later,

one that was built not just to represent the divine,

but to make you feel

like you were actually in the presence of God.

SHATNER: For centuries,

many have remarked on the strange power that Notre-Dame--

the historic cathedral that sits at the center of Paris--

has on people.

But what exactly is this power?

And could it actually be the presence of...

God?

DELL UPTON: What's extraordinary to me

is that you've got a building

that has been there for almost a thousand years,

in one form or another,

and even though it's important

from an architectural historian's point of view

in various ways, it also has this life in popular culture,

which many buildings don't.

Its role in the public view

has to do with its subsequent reputation.

AMIR HUSSAIN: You walk into Notre-Dame,

and all of a sudden you realize

the one human being is very small,

and you're literally humbled by this,

and almost falling to the ground,

because it's such an impressive sort of structure there.

YOUNG: The light coming through the windows,

especially the rose windows,

has an effect on our consciousness.

This is something beyond words.

This is the power of ritual and aesthetics to touch us

on a spiritual level.

It can't entirely be explained.

PICKNETT: It's like there is a presence there.

People go silent.

You know, talking in whispers.

And you say, "Well, of course they would be,

it's a Christian cathedral."

So that's what Christians take from it.

It reinforces...

their belief.

But millions upon millions of visitors have felt it,

whether they have any religion or not.

SHATNER: In 1163 AD,

Bishop Maurice de Sully authorized the construction

of Notre-Dame Cathedral.

The bishop wanted the majesty and splendor of Notre-Dame

to show France's devotion to God.

The massive building took over 180 years to complete,

and features a 115-foot-high roof

and two towers that stand 223 feet tall.

The value system of a collective

is reflected in the shrines and monuments they build.

Notre-Dame was the tallest building in Paris

for a very long time.

The common people on the street would look up

and see the cathedral towering above all other human activity.

That was the message.

A thousand years ago, when architects were building

bigger and bigger stone cathedrals,

the problem was, sometimes they would collapse.

So before they had steel,

they had to use stone with weight on the outside,

called the flying buttress, to support the roof.

That's the reason why Notre-Dame,

built a thousand years ago,

can have thin walls and stained glass.

BURROWS: Notre-Dame's builders wanted to inspire awe

when people came and looked at the cathedral.

So, how did they do that?

One of the main tricks is to allow light into the space

so that you get this huge sense of height.

You don't see the massive walls,

and the building seems to be floating on air.

SHATNER: Historians and architects

have also suggested that the power of Notre-Dame may come,

not just from how it looks,

but also how it sounds.

HUSSAIN: So, one of the amazing things about Notre-Dame Cathedral

is the sound, the acoustical properties.

And the acoustics in there are just marvelous.

[men's choir singing gently in Latin]

And that affects us.

It physically, literally affects us.

Our heart beats in a different kind of way.

You know, we can feel it in our bodies.

BURROWS: The great acoustics of Notre-Dame Cathedral came

from practice and understanding geometry.

So the people who did that, they understood

that if you emit noise, a singing, at one location,

through the shape of the ceiling you can bounce that noise

down to another location,

like a congregation inside the cathedral.

SHATNER: Did the builders of Notre-Dame

use clever engineering to create a sense of holiness

and spirituality in the cathedral?

Definitely.

But there are some who argue

that the site at which Notre-Dame stands

already possessed a special power

before the cathedral was built.

The location of Notre-Dame is significant.

Like many other cathedrals, it is a "temenos."

That means sacred place, sacred ground.

A place where we can be in touch with the transcendent energies.

COLLINS: One of the little-known facts

about the Cathedral of Notre-Dame

is that if you go outside of it,

there is a star on the ground

that points towards every point in France.

And it is from here that all of the measures

for cartography are made.

Which tells us that Notre-Dame

was considered to be the absolute center,

not just of France, but also of Paris itself.

HUSSAIN: There's a symbolism

to the physical location of Notre-Dame.

This idea that Notre-Dame radiates out,

not just from the center of Paris to France,

but from the center of Paris to the world.

SHATNER: A fire breaks out at Notre-Dame.

400 firefighters launch a valiant effort

to fight the blaze,

using water pumped directly from the Seine River.

[indistinct chatter]

Parisians watch in horror

as the flames and smoke envelop

the upper reaches of the cathedral

and its 315-foot-tall spire...

...collapses.

[panicked screaming]

COLLINS: A fire began in its timber roof

that spread quickly, causing the collapse of its spire

and hundreds of tons of lead melted and poured down

into the interior

of the structure.

And as much as a tragedy as this actually was,

the response to it across the globe was remarkable.

SHATNER: The reaction to the disastrous fire

transcended national borders and faiths.

In only two days, people around the world contributed

nearly a billion dollars

to rebuild and restore this beloved landmark.

YOUNG: The outpouring of donations from within France

and from all over the world tells us what a cathedral means.

It's not just a tourist spot.

If you enter a cathedral, something happens to you.

People know they felt something.

They are attached to that building.

HUSSAIN: So, when you had the fire in Notre-Dame Cathedral

and the rebuilding of that,

that was extraordinary.

The rebuilding of Notre-Dame Cathedral shows the attachment

that people have to the divine is infinite,

and I think there's a power there.

Can you explain it?

That sensation you feel entering a historic cathedral.

Ah. Do these cathedrals actually connect us to higher powers--

powers we might not fully understand?

Perhaps the answer can be found

by examining another vast man-made structure.

One that was designed with another kind of power in mind.

Power over Mother Nature.

SHATNER: With the country in the grips of the Great Depression,

President Franklin D. Roosevelt

presides over the dedication ceremony

of one of the most extraordinary engineering projects

in United States history--

the Hoover Dam.

McBRIDE: There were thousands of people.

And at that time, the people who came to listen to the president

dedicate it understood that it was more than just a dam.

They were standing on a structure

that they had built with their own blood and sweat and tears.

We are here to celebrate the completion

of the greatest dam in the world.

SHATNER: Named for President Herbert Hoover--

who was in office when construction began in 1931--

the Hoover Dam is located

in the Black Canyon region of the Colorado River.

Officials believed that a dam in this area

could help manage flooding of the Colorado River,

provide a much-needed reservoir of fresh water,

and be a source of hydroelectric power.

There was just one problem.

In order to tame the Colorado River,

the engineers would have to construct a more ambitious dam

than had ever been created before.

McBRIDE: Here you have the Colorado River--

one of the wildest and most untamed waterways in the world--

and you want to tame it.

You want to control it

so that you can provide dependable water storage,

hydroelectric power, irrigation.

MICHAEL DENNIN: Well, when I think of the Hoover Dam,

I'm impressed that we actually moved the river

to build the dam.

And they had to divert the river through tunnels,

through the mountainsides on either side,

so you have a dry bed that you can build the dam on.

And then bringing the river back just amazes me.

SHATNER: Built in just five years--

two years ahead of schedule--

the Hoover Dam is a staggering 726 feet tall.

At the time of its construction,

it was the tallest dam ever built,

the costliest water project ever undertaken,

and home to the largest hydroelectric power plant

in the world.

McBRIDE: Never before, ever in history, had there been

that much concrete placed and poured in one spot.

And enough concrete went into the construction of the dam,

you could build a two-lane highway

from San Francisco to New York.

SHATNER: The Hoover Dam changed the face of the nation,

allowing for the explosive growth of cities

like Las Vegas and Los Angeles,

and fueling the country's recovery

from the Great Depression.

But some have suggested that the Hoover Dam represents

not just an engineering success story

but also humanity's desire

to bend the forces of nature to our will.

McBRIDE: The construction engineer, Walker Young,

was widely quoted at one time as saying,

"The Lord put that canyon there, all we had to do was find it."

That speaks to a very kind of Judeo-Christian philosophy

that human beings were the paramount creatures,

and so we're going to impose our needs on nature,

and we're going to control nature.

LYNNE McNEILL: The flooding power of rivers

is something that humankind has been contending with

since there has been humankind.

And in a lot of ways,

the more we're able to restrain what have often been understood

as the unrestrainable forces of nature,

the more we suspect that maybe something superhuman

is taking place there.

SHATNER: Was the construction of the Hoover Dam

motivated by our need to harness, control,

and ultimately have power over Mother Nature?

There are many who believe that to be the case.

And as evidence, they point to a curious memorial

that was placed next to the dam.

An intricate celestial star map,

intended to send a message to future generations.

McBRIDE: The celestial star map is an amazing piece of art deco,

where laid into the ground,

is a star map with brass discs named after certain stars.

And the purpose of that

was really just one thing:

it was to fix,

in astrological time,

the very moment--

the month, the day, the minute, the second--

that Hoover Dam was-was dedicated.

SHATNER: The builders of the Hoover Dam certainly believed

that their creation would be an everlasting testament

to their triumph over the Colorado River.

But what happens when the forces of nature defy

our attempts to control them

in ways that we can't foresee?

McNEILL: Lake Mead is the man-made body of water

created by the Hoover Dam.

And what's interesting is that Lake Mead is actually

one of the most deadly recreational areas

that we have in this country.

People drowned mysteriously.

So many people end up dying there.

One of the fascinating things about Lake Mead

are these methane or gas pits.

And methane basically comes when vegetation decomposes.

Now, one of the things that Lake Mead did

is cover up a lot of vegetation, 'cause you make a lake

where there wasn't a lake before,

and what you had before was stuff growing.

So you can get these periodic releases

of the methane gas

that's been generated under the water

from the vegetation decomposing.

BARA: When the methane bubbles up to the surface,

what can happen is, if a boat is over that methane bubble,

it basically will lose all buoyancy

and just sink like a rock to the bottom of the lake.

So by building the lake over this land,

we may in fact have created a very dangerous situation,

and sort of set up the lake itself

to basically be a death trap.

I think if you reflect back to when the engineers

were making the Hoover Dam...

...it's often portrayed as trying to control nature.

The focus was on the dam,

and we probably weren't even asking questions

about the larger impact on nature,

'cause it would have been too hard

to calculate or worry about.

The challenge with engineering and science

is always the unintended consequences.

For the most part, people are driven

by this desire to make things better.

Are the tragic deaths at Lake Mead a warning?

That our relentless drive to build bigger, better,

and grander has gone too far?

If so, it's a warning that isn't being heeded.

If anything, mankind's determination to build bigger,

better, bolder is more evident than ever before.

It seems not even the sky is the limit.

SHATNER: After five years of construction, Burj Khalifa,

the tallest building in the world, is officially completed.

To celebrate this record-breaking achievement,

the United Arab Emirates

throws an extravagant opening ceremony

which features a massive fireworks display

and an elaborate light show

projected onto the gleaming tower.

KAKU: It's an incredible engineering feat.

The tallest building on the Earth.

It sticks out like a needle.

Everything else is pretty much flat,

and you have this needle

sticking right out of the desert.

SCOTT JOHNSON: The Burj Khalifa

is an exceptional building on many levels.

Most obvious is its height.

It's taller than any building in the world,

and it's taller by a whole lot.

SHATNER: At over a half a mile high,

Burj Khalifa bests the second tallest building in the world,

China's Shanghai Tower,

by a whopping 644 feet,

and is a masterpiece of contemporary engineering

and architectural prowess.

HUSSAIN: The fact that the largest building

is now in the Arab world, in Dubai,

is a great source of pride to people there.

So, there's really interesting connections

with the Burj Khalifa and Islam,

not just simply because you've got

the building built in a Muslim-majority country,

but also, you have an ancient connection

that the largest mosque in the world used to be in Iraq,

a ninth-century mosque built by the caliph Al-Mutawakkil,

the Great Mosque of Samarra, from the ninth century.

And what was really impressive about it was

the sort of winding staircase kind of minaret,

and that's what they've duplicated in the Burj Khalifa.

And so, I think for people in the Arab world,

it's almost a nationalistic competition--

who can build the tallest building in the world?

JOHNSON: Nation states have discovered that a tall building

can become a cultural symbol.

A symbol of pride,

a symbol of an ascendant economy,

a place in global states,

and a tall building seems to resonate with that.

BURROWS: We're currently in a race

to build the tallest structures on Earth.

And the question for me is,

what is the limit to how high these things can go?

McNEILL: Human beings have always strived

to break their own records,

and when we can achieve an architectural feat

that is breaking all of the records

of any previous architectural feat,

we are saying something

about our ability to overcome limitations.

SHATNER: At 481 feet,

the Great Pyramid of Giza stood as the tallest structure

in the world for over 4,000 years...

...until it was surpassed by the old St. Paul's Cathedral

in London in the 13th century.

But it wasn't until steel was invented

that the first skyscraper was erected in Chicago in 1885,

and a new kind of building boom began.

One that saw the completion of the Empire State Building

in 1931, and shows no sign of slowing down.

HUSSAIN: For human beings to go up

isn't just to go up and be able to see commanding views.

Why do we build these buildings?

Because we want to get up into the heavens

because the heavens are the divine realm.

It's being able to go up and see

what would God's-eye view look like?

SHATNER: To see things as God does?

But is that a good idea?

After all, there's a famous story from the Bible

that serves as a cautionary tale against doing just that.

In Genesis, chapter 11, you have the story

of the Tower of Babel.

Human beings are united, they speak the same language,

and they build this tower to go up into the heavens,

and you have God saying, "Wait a minute,

"what are these people doing?

"They're gonna build this

and they're gonna come up to where I am."

And so, God basically confounds these people

by having them speak different languages,

so they're not able to understand each other.

So they're not able to build this thing

because now all of a sudden,

they don't speak the same language.

McNEILL: The Tower of Babel is a story

of trying too hard to go too far,

and paying the price for that.

And it's interesting for us to look at our modern

architectural marvels,

as potentially containing that warning, or that threat.

So many people have made a likeness

between the Burj Khalifa and its shape...

...and the Tower of Babel.

The Tower of Babel as we remember it

was supposed to be a spiraled tower

that was going to reach to the heavens

so that people could see God.

That was considered inappropriate

and too much hubris.

I think we're operating within the constraints

of engineering science,

but somewhere out there is a limitation,

and I think we're approaching a limit.

SHATNER: As we seek to build ever higher,

is there a danger that what we think of as ambition...

...may in fact be hubris?

Or is it simply an attempt to reach for the sky,

to see how high we can climb and how far we can go?

Perhaps even to the stars?

SHATNER: The first module of the International Space Station

is launched into orbit on a Russian rocket...

...beginning arguably the most groundbreaking

engineering project in human history.

The International Space Station

is really a marvel of engineering.

It took 42 flights to build this thing over ten years...

...and it was sent up module by module,

with astronauts and cosmonauts living on board

and adding to it as it became a larger and larger space.

TOM SPILKER: It has a set of solar arrays,

and from tip to tip, each one of those eight wings is 239 feet.

So it is 357 feet long.

NASA likes to say it's one yard short

of being an American football field

including the end zones.

TEITEL: The International Space Station

is the symbol of how incredible

human ingenuity and engineering really is.

That we've been able to not only

build the International Space Station

but keep it alive for 20 years

and learn so much in the process,

is really an incredible outlet of what humans can do.

SHATNER: The idea of a space station

suitable for human habitation

started with the vision of one man,

Dr. Wernher von Braun,

the German-born aerospace engineer

who designed the Saturn V rocket that took Americans to the Moon.

In 1952, nearly a decade before the first manned spaceflight,

von Braun's concept for a 250-foot wheel-shaped station

captured the world's imagination.

SPILKER: Von Braun envisioned

this rotating space station to provide

a certain amount of artificial gravity.

It could be used for monitoring Earth,

weather, for military purposes.

Also as a way station for docking a spacecraft

that would be going somewhere else in space,

to the Moon or to Mars.

TEITEL: So the International Space Station

isn't quite that.

But it's the proof of concept,

and starting to help us understand the technology

such that maybe down the line, the next generation

or the generation after the next,

we will eventually get that giant city in orbit.

SHATNER: A giant city in space?

It's a marvelous and inspiring idea,

one that raises a profound question:

have we achieved all that we can on our home planet?

And are we destined to leave our mark

not just on Earth but far beyond it?

So many of our iconic structures on this planet

are reaching beyond, stretching up from the surface,

trying to get us somewhere else.

Once we're in space,

what form will our structures have

and what role will they play?

Not just pragmatically as shelter for us,

but as symbols for us?

And what will we reach for

if we're already off of this planet?

Whether it's the giant stone monuments of the ancient world

or the awe-inspiring cathedrals of the Middle Ages

or modern feats of engineering that are all around us,

humans possess an incredible ability and desire

to build and to make us wonder.

So, where do we go from here?

What are we going to build next?

Well, that, my friends, is something

that is only limited by our imagination

and our determination to impose order on Mother Nature.

And our desire to explain...

...the unexplained.

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