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00:01It's one of the most magnificent cities of the ancient world.
00:06Petra.
00:08Its monumental temple-like tombs soar over a hundred feet tall.
00:14And these wonders of engineering are not constructed.
00:18They're carved out of sandstone cliffs.
00:23At its height, Petra was the center of a vast trading network in frankincense and myrrh.
00:28And home to over 30,000 people in one of the most bone-dry deserts on earth.
00:36It's not an appropriate location for a city.
00:40There is not even drinking water down there.
00:43How did an ancient people supply enough water for this vast city?
00:49And how did they carve these magnificent structures so high up in these cliffs?
00:58To find out, a geoscientist teams up with stonemasons to carve a Petra-style tomb.
01:05We're looking at something that hasn't been witnessed for almost 2,000 years.
01:10And archaeologists and hydroengineers discover how a group of nomads transformed this desert city into an oasis, the Las Vegas of the ancient world.
01:21It's really conspicuous consumption of this precious resource, water, in this desert environment.
01:27Finally, after 2,000 years, the secrets of Petra are about to be revealed.
01:34Up now on NOVA, Petra, Lost City of Stone.
02:04It's one of the driest places on earth.
02:17Yet concealed among the canyons of this harsh desert in the kingdom of Jordan is a magnificent ancient city.
02:28Petra.
02:32For over 1,000 years, its location remained hidden, protected by fortress-like cliffs and Bedouin tribes who fiercely guarded its secret.
02:45Then, in 1812, a Swiss adventurer disguised as an Arab pilgrim risks his life to search for the legendary city.
02:58Johann Ludwig Burckhardt makes his way through the Sique, a dramatic canyon rising almost 600 feet that twists and turns for nearly a mile.
03:09Near its end, the canyon widens to reveal a towering, temple-like façade.
03:22It is called the Treasury, or Qasne in Arabic.
03:28Built 2,000 years ago, it is a masterpiece of design and engineering.
03:34Majestic columns rise from the canyon floor, topped by ornately carved capitals.
03:44Statues of mythological figures adorn its façade.
03:49A fanciful urn graces its roof, and a towering doorway leads inside to a room with three chambers.
04:00Here, there is no elaborate carving, just the simple, natural beauty of the stone.
04:10And then we back away and we realize, not only is this building unique and fantastic, but it has been carved into the sheer face of living rock.
04:19The Treasury is actually a sculpture on a monumental scale.
04:27At 80 feet wide and 127 feet tall, it is twice the height of the Mount Rushmore Memorial.
04:34As Burkhart continues through the canyon, he discovers hundreds of magnificently carved façades everywhere.
04:44Many rivaling the grandeur of Egypt, Greece and Rome.
04:48Greece and Rome.
04:52But there is more.
04:54The ruins of an entire city.
04:59A 6,000 seat theater carved right out of the sandstone.
05:05A main street lined with huge temple-like structures.
05:08And even more spectacular monuments carved higher in the mountains.
05:19But Burkhart's rediscovery of the legendary city sparks more questions than answers.
05:26Who built Petra and why?
05:29Burkhart was inspired by stories of a mysterious desert tribe who gained their wealth trading spices and silks among China, India, Egypt and Rome.
05:45And then hid their treasures of gold in the cliffs.
05:51Greek and Roman sources provide a name for these people.
05:55The Nabataeans.
06:00An account from the 4th century BCE describes the Nabataeans as nomadic tent dwellers.
06:09But three centuries later, another source describes them as a sophisticated people inhabiting a prosperous city.
06:19Around the time of Jesus, Nabataea is a thriving kingdom surrounded by Egypt, Judea and the vast North Arabian desert.
06:27How, in just a few centuries, did a village of tents become a wealthy kingdom?
06:38And how, in the middle of a desert, did they build Petra?
06:43Tom Paradise has spent over three decades trying to find out.
06:53He's a geoscientist who specializes in preserving ancient structures.
07:00Alongside the treasury, he sees strange square marks that could be a clue to how it was built.
07:06Are these marks the remnants of where an ancient scaffold was anchored to the cliff face?
07:13For many years, people considered these to be holds for wooden scaffolding that may have been used for the actual carving.
07:21But Paradise has doubts.
07:25If these are scaffolding marks, why did the Nabataeans leave them here?
07:30And why are they found nowhere else in Petra?
07:34Paradise believes the real reason for the marks may be tied to the fanciful name given to this monument centuries ago.
07:41This building is called the Khazne. It is the treasury.
07:47And so, legend goes back millennia that this housed riches.
07:52Because it is known as the treasury, people have searched it for treasure.
07:57Bullet holes riddled the urn at the top.
08:00And these marks may be footholds to climb up and get a closer look.
08:07We think maybe those footholds were carved for the purpose of raiding the upper parts of the Khazne, looking for the treasure.
08:15But the urn holds no gold. It's solid rock.
08:20The only treasures here are the magnificent sculptures.
08:24Whatever the true purpose of these marks, Paradise is certain they're not for scaffolding.
08:33After all, in this desert, wood is relatively scarce.
08:39So how on earth could the ancient Nabataeans carve such a huge monument so high up in the cliff face without scaffolding?
08:49Paradise has a bold plan to find out.
08:54They go all the way down to the top.
08:58Working with a team of stonemasons, they will try to carve a Nabataean style facade for the first time in 2,000 years.
09:08I may be sitting on the answer to the age old question as to how were these facades carved?
09:13At the same time, archaeologists and hydro engineers are investigating how the Nabataeans could even survive in this bone dry environment.
09:22The entire hydraulic infrastructure was built, as I think I may prove, following one master plan.
09:31Their groundbreaking discoveries are revealing the engineers of Petra were not only masters of stone, but also of water.
09:38transforming a desert city into the Las Vegas of the ancient world.
09:47Now, can scientists finally uncover how a nomadic tribe built this city of stone?
09:53and why Petra ultimately vanished into legend?
09:59most people will recognize the treasury from the climactic scene of Indiana Jones and the Last Crusade, where Harrison Ford and Sean Connery enter a secret temple to discover the Holy Grail.
10:23But despite the great Hollywood story, the treasury and most of Petra's iconic buildings are not temples.
10:34They're tombs.
10:38The Nabataeans left very little writing.
10:40But on some of their facades are inscriptions in an Aramaic script, the common language of the Middle East in the time of Jesus.
10:50This one, on a facade called Turkmenia, reads in part,
10:54This tomb is sacred.
10:57Nothing of all that is inside shall be changed or removed forever.
11:03Tomb raiders disregarded notices like this, so human remains and grave goods rarely survive.
11:10But body size niches leave no doubt these were burial chambers.
11:15In all, the cliffs of Petra hold over 800 tombs.
11:24The prominence of these monuments led many of the early explorers to consider the possibility that this might just be a city of the dead, a necropolis.
11:34But over the past 200 years, all of the research has actually shown it was a city of the living as well.
11:39Chris Tuttle has been working here more than 10 years.
11:45Although less than 2% of the site has been excavated, archaeologists have mapped and surveyed the area.
11:52All in all, ancient Petra was a metropolis about the size of the island of Manhattan.
11:58There is a two square mile downtown where people lived, worked and prayed.
12:03Suburbs, housing more people, stretch to the north and south.
12:11Based on these surveys, Tuttle can estimate the population.
12:16At its height, we expect this city to house somewhere between 20,000 or 30,000 people.
12:23Yet unlike cultures that bury their dead in isolated areas, in Petra, tombs are everywhere.
12:30Why did the Nabataeans carve their tombs throughout the city?
12:37And how did they do it?
12:39Paradise hopes his carving project will provide some answers.
12:43Creating an experiment in which we reconstruct a facade will give us insight into how the Nabataeans carved these fantastic facades 2,000 years ago.
12:54But Paradise can't carve his facade here.
13:00Petra is a protected World Heritage Site.
13:03He must find a cliff face with the right kind of sandstone somewhere else.
13:13His search takes him a world away to Southern California.
13:16Looks like a promising prospect.
13:18Yeah.
13:20While the ocean view is a sharp contrast to the Jordanian desert, the sandstone is identical to Petras.
13:28Paradise enlists stonemasons Blake Rankin and Nathan Hunt.
13:33With permission from the landowner, they search for just the right rock.
13:40Hunt is a classically trained master carver and architectural sculptor with over 18 years of experience.
13:48We're looking for a fine-grained sandstone which lends itself to ornamental carving.
13:54Sandstone is a soft rock made of compressed layers of sand and minerals.
13:59That looks like the type of stone we're looking for.
14:02Yeah, this is great.
14:03It looks like it's going to carve really well.
14:06The team has found the perfect rock and cliff face.
14:10Now, they must find the right tools for the job.
14:16Back in Petra, Paradise discovers a clue in the stone.
14:21Chisel marks made from iron tools.
14:23The technologies used with chisels and stonework haven't changed in 2,000 years.
14:29We use the same chisels.
14:31And so, they leave the same marks.
14:34By matching modern-day tool marks with those found in Petra,
14:39their advisor, Tom Paradise, tells them exactly which tools to use.
14:44The claw chisel, the flat chisel, and the pointed chisel.
14:52The pointed chisel is used for the coarser chiseling that removes large amounts of rock.
14:59So, the pointed chisel is exactly what Hunt and Rankin used to begin work.
15:05Yeah, feels good to be carving.
15:07But their exuberance fades fast.
15:11Carving by hand is seriously slow.
15:15There's no way we can do it by hand.
15:18A Greek source says the Nabataeans had few slaves,
15:22but they probably did have plenty of skilled manpower and time.
15:29Hunt and Rankin have neither, but they have power tools.
15:36Whoo!
15:38Even so, Rankin insists they're not cheating.
15:41This is a chisel very similar to one that the Nabataeans would have used.
15:45The only difference is that we've mechanized the hammer process
15:49so that we can move a lot of stone really quickly.
15:54The carvers have found the right rock and the right tools for the job.
15:59As Hunt and Rankin prepare the cliff face, Paradise must decide what exactly to carve.
16:08What makes a Nabataean tomb Nabataean?
16:13Many of the facades in Petra actually look like to belong somewhere else.
16:19At the treasury, Paradise finds statues, columns, and capitals reminiscent of ancient Greece and Rome.
16:26And across Petra, he finds architectural features from other far-flung empires.
16:34A steppe design associated with Assyria and Mesopotamia.
16:39Elephant-headed capitals evoking India.
16:43Even Egyptian obelisks.
16:46But among the familiar are designs Paradise has seen nowhere else.
16:56There's a pediment on the top that is split in the middle, capped by a cone, a capital, and an urn at the top.
17:04This isn't Greek. This isn't Roman.
17:08This new design is seamlessly mixed with features from far-off cultures.
17:12The architecture is the synthesis, and this begins to tell us a story that is the real Petra.
17:21What makes a Nabataean tomb Nabataean is the combining of their own unique style with designs from other empires.
17:29But how did these people in the middle of the desert come into contact with such far-away places?
17:38Two words. Frankincense and myrrh.
17:43Frankincense and myrrh were must-have luxury items in antiquity.
17:53In the New Testament, they are among the gifts the three kings bring to the baby Jesus.
17:59Made from dried sap from trees in the southern Arabian Peninsula,
18:04they were burned obsessively in religious ceremonies in Egypt, Greece, and Rome.
18:09But to get that incense to consumers throughout the Mediterranean, it first had to be transported through the desert.
18:20After centuries of living as nomads, the Nabataeans knew every secret source of water.
18:30If you wanted to cross the desert and make it out alive, you had better have a Nabataean leading the way.
18:43Along the route, they built outposts to guard their goods and extract a toll.
18:48In a valley just over the mountain from Petra, Andrew Smith has excavated this fort called Bir Makur.
18:58There was definitely a Nabataean presence here, most likely related to the trade that came out of Petra.
19:06Among the artifacts he excavated are dozens of tiny clay perfume bottles.
19:12The Nabataeans were most likely processing some of the raw frankincense.
19:17They would have bottled and then packed them tightly so that they weren't going to break
19:22and probably loaded them on camels or even donkeys.
19:27The incense road became the lifeblood of the Nabataeans,
19:32pulsing from Saudi Arabia to the port of Gaza, the gateway to Greece and Rome.
19:37The financial reward from this trade catapults a desert tribe into a powerful kingdom.
19:50Nabataean towns and tombs spring up throughout the northwestern Arabian Peninsula.
19:58By the first century, the Roman writer Pliny called the Nabataeans the richest race on earth.
20:05Much of their wealth went into building their capital city, Petra.
20:18Tom Paradise believes the Nabataeans' far-flung trade connections influence their domestic designs.
20:25Because Petra is a crossroads for the region,
20:28it makes sense that they would adopt and adapt different architectural styles from a lot of their trading partners.
20:36But with all these different styles, what should Paradise pick for his carving experiment?
20:42This sort of facade represents more than 500 other facades in Petra.
20:50So this style really is the archetype of the tomb facades.
20:55To Paradise, this tomb is typically Nabataean.
20:58Although it appears plain, it's a mashup of different architectural styles.
21:05It has the remains of a Greco-Roman doorway, Nabataean capitals, an Egyptian cornice,
21:14and a design from Assyria that may represent a stairway to heaven, called a crow step.
21:19But when the carving team transfers the design to California, it isn't wide enough to fit the rock.
21:27You never really know how it's going to work in the stone until you get started.
21:31We think it's going to look a lot better if we widen the facade.
21:36But how will making the facade wider affect the design?
21:39Make each block of the crow step seven by seven inch.
21:44This would be the edge of the crow step. That would be great.
21:47Grappling with this problem, the team may shed light on a mystery that has confounded scholars for decades.
21:54Why do Nabataean tombs, while similar, have unique variations?
22:00There's one motif they modify a lot, and that is the crow step.
22:05Why the difference? We've never really understood.
22:07Some of the tombs in Petra have crow steps that reach all the way down to a narrow ledge called the cornice.
22:15Other crow steps meet in the middle.
22:19Some scholars have argued this reflects an evolution in design.
22:25But Paradise thinks they have struck upon a practical reason.
22:29As we make the facade wider, it really requires us to take the crow steps all the way down to the cornice.
22:37If the facade is wider, the crow steps must break apart.
22:44Increasingly we notice that changes of the rock actually cause changes within the design elements.
22:51I think we have to give more credit to the rock than we have in the past.
22:56Sort of roughly about nine inches on there.
22:58By carving their own facade, they discover a basic principle of Petra.
23:04The rock influences what they carve and where they carve it.
23:08But why here?
23:09Choosing to build their capital in the middle of a rocky desert poses another age-old question.
23:21How did the Nabataeans get enough water to support such a magnificent city?
23:26One clue is here in the city center, at a structure known as the Great Temple.
23:36Its monumental stairway leads to a large stone platform surrounded by over a hundred columns.
23:43Holes in the courtyard show there are channels running underneath them.
23:52It's running under the paved floor.
23:54Oh, that'll do it.
23:56Sue Alcock leads a team from Brown University to investigate.
23:59If we could make all this surface architecture go away, you know, just kind of magically lift it up and look down,
24:07I think we'd see quite a network of these channels and canals.
24:12She may be short on magic, but Alcock does have another way to look below the surface.
24:18A technology called GPR, Ground Penetrating Radar.
24:23Excavation is inherently destructive.
24:25This is a way to get a look at what's down there in the same way you would go in for an x-ray perhaps before you went in for a surgery.
24:33The radar sends a high-frequency radio wave into the ground.
24:38When the wave passes through different materials, like from stone to soil, part of the wave is reflected back.
24:46But the speed of the wave changes depending on the material, slower for soil, faster through air.
24:57Detecting these changes is how the GPR sees where the channels are.
25:02The team systematically drags the radar back and forth across the courtyard.
25:10There's some kind of a channel right there.
25:13Yeah, look at that.
25:15Beneath the great temple is a network of channels that looks like plumbing.
25:21Intriguingly, the channels seem to extend beyond the courtyard.
25:26When we look at Petra, we often tend to think about building by building.
25:31And I actually think it was all tied together.
25:34Alcock believes these channels are evidence of a massive citywide water system.
25:40Petra was an urban center and it had urban water supply.
25:44There's just one problem with this theory.
25:48Petra is in one of the driest places on the planet.
25:55If the great temple is indeed the heart of a vast engineering system that supplied an entire city with water,
26:02where is all that water coming from?
26:04One possible source is still used daily by locals.
26:18It's called Ein Musa, or the Spring of Moses.
26:22This is it.
26:24Alison Mikkel and Cecilia Feldman of Brown University's survey team join hydro engineer Charles Ortloff to investigate.
26:30In Numbers 2011, it talks about how the Israelites were wandering in the desert,
26:36and Moses strikes this rock in anger, and water flows forth.
26:40The story of Moses miraculously bringing forth water has been linked in legend to this rock and spring.
26:48But it would take an engineering miracle to get this water from Ein Musa to Petra's city center.
26:54It's five miles away.
26:56In the Sikh, the entrance to Petra, the team finds evidence for how the water may have been brought here.
27:11Running along the side of the path is a narrow channel which has imprints of what were once enclosed ceramic pipes.
27:18If you look inside of the channel, you can see the actual imprints of ceramic sections that are roughly about a third of a meter long.
27:31At roughly a foot long, it would require tens of thousands of segments to create a five-mile pipeline from Ein Musa, high in the mountains.
27:40And every one of those joints would have the potential to spring a leak.
27:50Could the Nabateans possibly have pulled off such a feat of hydroengineering?
27:54At California State University in San Jose, Charles Ortloff and graduate student Cheyenne Misra-Hosseini are trying to figure that out using this 26-foot tank.
28:10Water is extremely precious to the Nabateans, so ancient engineers need to design a pipeline that would be free of leaks.
28:24Their challenge, and Ortloff's, is how to get water to flow through a pipe as quickly and efficiently as possible.
28:32The different angles represent different choices.
28:37One choice seems obvious. Make the slope of the pipe steep.
28:42Ortloff sets the slope to six degrees and turns on the water.
28:49Things start out well.
28:54The water is flowing fast.
28:57But it fills the pipe too quickly, producing an area of turbulence known as a hydraulic jump, which causes the water flow to slow down.
29:09This is the hydraulic jump right here.
29:13But there's a bigger problem.
29:16The pipe is now filled with water, raising the pressure.
29:20In the ceramic pipelines, that pressure could create leaks at the joints.
29:31So that design, where we have the steepest slope, is not good.
29:35Okay, closing all the valves.
29:37If you could put the brick on the other side, just gonna slide it over.
29:42Ortloff adjusts the slope of the pipe to four degrees.
29:45Ah, a little more.
29:46Ah, there we go. Got it.
29:50A small change in the slope, just two degrees shallower, has a big impact on the speed of the water.
30:01The big surprise here is that we have only changed the slope by two degrees, and yet we have a completely different flow pattern.
30:09The flow is fast, and in this test, the pipe never completely fills with water, which would be good news for Petra's plumbers.
30:20The entire flow has an exposed airspace above the surface, and this will prevent leakage in the system.
30:28With the help of modern-day tools, Ortloff has shown that the best design for delivering water fast and leak-free is a four-degree slope.
30:41And when Ortloff measures the angle of the carved channel in Petra, he makes a remarkable discovery.
30:47If we look at actual field measurements, we're able to see that with their pipelines, the ancient Nabataean engineers had a slope of approximately four degrees.
30:592,000 years ago, Petra's engineers worked out the perfect design for their long-haul pipelines.
31:06They invented scientific principles that were only officially discovered in the West some 2,000 years later.
31:17It is clear that the Nabataeans were master hydraulic engineers.
31:22But water is not the only scarce resource in the desert.
31:33Wood from local trees was also in short supply.
31:37So how could the Nabataeans build their tombs so high up in the cliff face without using large wooden scaffolding?
31:45Paradise finds an important clue in this unusual carving.
31:50Aptly called the unfinished tomb.
31:55The top is finished.
31:57The upper area of the capitals remains somewhat crude and still in progress.
32:02But then below that, nothing has been carved at all.
32:06It's the natural sandstone face.
32:11To Paradise, the progression of finished at the top and barely started below can mean only one thing.
32:17The Nabataeans started from the top and carved down.
32:22The unfinished tomb shows that Nabataeans began by sculpting the top layer of the facade and then worked their way down the cliff face.
32:34Windy again.
32:39Back in California, Paradise tells Hunt and Rankin they must carve their facade Nabataean style, top down and without scaffolding.
32:48There's a lot of challenges involved in trying to figure out how the Nabataeans carved a piece like this.
32:56I die like a Nabataean is my worst fear.
32:59Falling off the rock.
33:01Up to now, they've been using safety harnesses.
33:06But the Nabataeans top down approach gives them an ingenious idea for how to carve without harnesses or a large wooden scaffold.
33:15We've drilled into the stone here and placed a couple of pins and then put a plank on top and created a temporary and moveable ledge.
33:28It doesn't require a lot of material.
33:29They drive three pins into the rock and lay just a couple of planks of wood across them, forming a platform.
33:40As their carving descends, it erases the holes they've made, leaving no sign of their platform.
33:47By the time we get to the bottom, we've pretty much removed all evidence of any plank.
33:51The pin and plank solution works perfectly.
33:56It could explain how the Nabataeans were able to carve so high up without scaffolding.
34:02And why no evidence for the technique can be found.
34:09Halfway through the carving, the team makes another discovery.
34:13We can move a lot of stone really quickly with these chisels.
34:16We've been moving a surprising amount of stone every day.
34:21A little carving creates a lot of rubble.
34:26I really cannot believe that much carving produced this much rubble.
34:30The rubble has formed a ramp.
34:34This means they don't need their platform anymore.
34:37Now they can just walk up to the facade.
34:40When we see this much material being produced from the carving,
34:42we now realize that we create ramps from this rubble that gives you access to the facade for the stone carvers.
34:50Combining the clues found in Petra with the discoveries in the carving project,
34:56a new theory emerges for how the Nabataeans may have carved the treasury.
35:03They begin by climbing to the top.
35:05Here, they cut a narrow ledge into the cliff face.
35:10Using ancient drills, they fix pins below the ledge and lay planks across to provide a platform for the carvers.
35:20The first thing they carve is the urn and the upper layer of the monument.
35:25They work their way down, sculpting the split pediment and the magnificent statues.
35:33About halfway down, the debris from the carving forms a ramp.
35:40Now, the carvers can walk up to the facade and continue carving the elaborate capitals and the handsome columns.
35:48We don't know of any other culture or society using this kind of engineering technique for this scale of construction.
35:59The top-down approach turns out to be a brilliant innovation for carving these tombs in Petra's sand-sewn cliffs.
36:06But carving is only part of the treasury's grandeur.
36:16Its impressive location commands the head of the canyon and the entrance to the city.
36:25Yet the same narrow canyon that creates this dramatic reveal can also be a death trap.
36:35These amateur videos capture a rare but deadly desert hazard.
36:45Flash floods.
36:48Petra's average annual rainfall of just a few inches can hit all at once and pour down this gorge with lethal force.
36:57Flash floods took the lives of 22 French tourists here in 1963.
37:03And even today could damage the treasury.
37:06Willi Bellewald, a Swiss architect and archaeologist, has come to Petra to protect both tourists and the treasury.
37:18He's searching for clues to how the Nabataeans held back the floods.
37:22When they decided to carve this facade into the cliff, they had to do something against flash floods in wintertime.
37:32Next to the treasury is a narrow gorge.
37:36Here, Bellewald finds huge blocks mortared together to form an ancient dam.
37:40It's 2,000 years old and still totally preserved.
37:48But this one dam would not be enough to protect the treasury.
37:52So Bellewald is on the hunt for more dams.
37:55While the landscape appears to be plain rock, to Bellewald it is packed with clues.
38:04He notices different colors on the canyon wall.
38:09Above this line, the stone is dark.
38:13Below, it's lighter, which Bellewald believes is caused by mineral deposits from water once stored here in a reservoir.
38:21Following this water line brings him to an area where two deep grooves have been carved into the canyon walls.
38:31The grooves show where a dam once stood.
38:36All these dams had to be anchored into the cliffs on both sides that they could easily withstand the pressure of the retained water.
38:46Following these clues, Bellewald has uncovered an ancient Nabataean dam system.
38:56The Nabataeans built five dams.
39:01And to make those dams even more effective, they carved a channel 140 feet long and 16 feet deep to reroute some of the water.
39:12This created a large area to store overflow and reduce the force of the water before it reached the treasury.
39:22It's an engineering feat almost as impressive as the treasury itself.
39:27They realized that if they divert the water, they allowed the water to spread out to a much bigger surface and this reduced its speed tremendously.
39:40It worked perfectly.
39:42So perfectly, Bellewald can't improve on this design.
39:49Today, a team is repairing this ancient dam network so it can once again protect the treasury.
39:57If we want to keep the treasury for the future, we have to protect it again as 2,000 years before from flash floods and that's exactly what I'm doing.
40:10Because the threat of floods was so great, Bellewald believes the Nabataeans must have built the dam system and the treasury at the same time.
40:20In fact, scholars now believe the grand tombs, the city center and the water systems, most of the ancient city of Petra were built within 100 years around the birth of Jesus.
40:35The entire hydraulic infrastructure of Petra was built following one master plan.
40:41So just how much water did that system provide?
40:48Back in San Jose, Charles Ortloff is figuring that out.
40:53These are the main supplies of water from all of the cisterns, all the dams.
40:59Ortloff has mapped every water feature he and other archaeologists have discovered.
41:04Eight springs for fresh drinking water.
41:07Thirty-six dams to protect the city from flash floods.
41:12Over 100 cisterns and reservoirs to collect and hold rainwater.
41:17And 125 miles of pipeline to connect many of these features into one integrated water system.
41:26From the map and his flume experiments, Ortloff can estimate the total amount of water available to Petra's 30,000 people.
41:34If you sum up all of the water from various sources, that would lead to eight liters per person per day.
41:45Eight liters is about two gallons.
41:48In a world before showers and washing machines, that's more than enough water to survive on.
41:53In fact, new discoveries revealed that the Nabataeans had enough water to transform Petra into a desert oasis.
42:04Evidence of that water surplus is being found right next to the great temple, in a large open terrace.
42:10It was named by early explorers as the marketplace.
42:20So when Leanne Bedal began digging here in 1998, that's what she expected.
42:26Because it had been called a marketplace, I came in prepared to excavate a market.
42:31But as she began digging, at eight feet deep, she discovered waterproof cement.
42:38So we knew that we had something containing water or something deep.
42:42Her team excavated further and discovered a subterranean structure.
42:47We have the southwest corner here, and directly to the north is the northwest corner.
42:52Bedal located all four corners to discover overall dimensions of 140 by 80 feet, nearly the size of an Olympic swimming pool.
43:06Then, in the middle, she found evidence of a stone platform, and surrounding the sunken structure, channels.
43:14Likely used for irrigating a lower terrace, where soil samples suggest the area had been cultivated.
43:23When she puzzles the evidence together, Bedal concludes the marketplace was, in fact, a huge ornamental pool complex,
43:32including an island pavilion and a garden on a terrace below.
43:36If you can imagine below us this large pool of water, and then a green garden with date palm trees and flowers.
43:47This is something that is for showing off.
43:51Throughout the city center, archaeologists are finding other decorative water features, like fountains,
43:58and a canal running beside a colonnaded street.
44:01It's really conspicuous consumption of this precious resource, water, in this desert environment.
44:09Conspicuous consumption of water in the middle of a desert?
44:14It seems Petra resembled another flashy desert destination.
44:18A great comparison is Las Vegas, where you have this very arid desert surrounding this oasis city,
44:33where everywhere you go you see the use of water, fountains.
44:39By diverting a precious resource into a wealthy center, it sends a message to anybody who sees it,
44:46that this is a place of wealth and power.
44:50For ancient visitors, after days of traveling on camel through the hot parched desert,
44:56entering this oasis city must have made a powerful impression.
45:03Petra's luxurious pools and internationally inspired architecture
45:08likely sparked the legends that echoed through the ages.
45:12Back in California, after two months of carving and nearly 2,000 years,
45:25architecture of far-off lands emerges from the rock.
45:31We've got Assyrian, Egyptian, Greco-Roman, but you put it together, you stand back, and it's Nabataean.
45:36And now it's a little bit Californian.
45:39That's right.
45:43Whether the Nabataeans were carving tombs for the dead or water channels for the living,
45:49their mastery of stone was the key to Petra's wealth and beauty.
45:54So why did the Nabataean kingdom decline and Petra largely disappear?
46:11Across the city, collapsed columns point to a prime suspect.
46:16Ancient texts record a huge earthquake in 363.
46:20As a result, for a while, when archaeologists came to Petra,
46:24any time they saw something like this, they'd say,
46:27ah, this fell out in 363.
46:29But one catastrophic earthquake does not provide the whole picture of the city's decline.
46:35At the Great Pool, the most luxurious place in Petra,
46:41there's evidence that hard times hit the city even earlier.
46:44It may have been as early as the second century, because at that point we find a lot of animal bones at the bottom of the pool,
46:52so it seems to have been used for trash.
46:55Found in the Great Pool, this layer of fallen rocks dates to around the 363 quake.
47:00But below that, the layer of soil containing the animal bones indicates the pool filled in at least 100 years before.
47:11And there is evidence of more destruction 100 years after the Great Quake,
47:16which may have fatally weakened the city's protective dams.
47:19Large sections of Petra's main street are missing pavers.
47:28Tom Paradise believes they were washed away in a catastrophic flash flood.
47:35The floodwaters rushed down through Petra city center, ripping up cobblestones.
47:40This flood inundated the city and may have marked the end of Petra's golden age.
47:51Ironically, the very water that brought life to Petra may also have contributed to its demise.
47:58Today, in the hills of Southern California, the carving team is bringing a bit of Petra back to life.
48:17The final flourish will be a feature not found in other cultures.
48:22A Nabataean-style capital with a simple knob in its center.
48:29Normally, there is a detail here.
48:32Typically, there is a leaf or a flower here.
48:36You never really see it left in this very abstract form.
48:41It's quite beautiful in its simplicity.
48:45Paradise believes the Nabataeans choose this simple form out of respect,
48:49almost reverence for the sandstone.
48:53Their sense of the rock as a living material that had to be sort of caressed and worked
49:00was really as remarkable as their engineering expertise.
49:05And the sandstone itself becomes a tool to finish the surface of the tomb.
49:11Using the same stone that we carved off the rock,
49:13I'm just rubbing the last little stages.
49:17Just kind of carefully finishing off that last surface.
49:33Stone is at the core of Nabataean lives.
49:36The very name for their city, Petra, comes from the Greek word for rock.
49:43The Nabataean relationship with their sandstone was fundamental to who they were.
49:50They're born in this valley of rock.
49:53They live in this valley of rock.
49:56And then when they die, they are buried in the rock itself.
49:59These hewn tomb facades become their final resting place.
50:08Each year, over a half a million tourists retrace the steps of the explorer Johan Ludwig Burkhardt.
50:25And gaze up in awe at the treasury.
50:35But in the two centuries since Petra was reopened to the Western world,
50:41its distinctive engineering and culture is proving equal to that of any ancient civilization.
50:47Petra is more than a city.
50:49It was the seed of a kingdom.
50:53A kingdom whose peace and prosperity was the envy of the ancient world.
50:57Cisterns, channels, dams, even fountains and pools.
51:04The Nabataean mastery of water fueled their astonishing city of stone.
51:11The water features are underpinning everything.
51:13If the Nabataeans couldn't control this water, you wouldn't have a city here.
51:17Over 2,000 years ago, a desert tribe settled among these forbidding cliffs
51:23and transformed this hostile landscape into an oasis.
51:28The Nabataeans learned how to maximize these limited resources
51:32to produce a society and a culture that thrived and prospered for hundreds and hundreds of years.
51:38Burkhardt came here chasing legends of a city lost in the sands of the desert.
51:47A city with riches from all over the known world.
51:51Buildings that rivaled Egypt and Rome.
51:54And fountains and pools overflowing with water.
51:57Today, it's clear many of the legendary splendors of the lost city of Petra are true.
52:27Funds over environmentally santé.
52:37Etc.
52:40MS.
52:44com
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53:24.