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00:02The giant stone obelisks of ancient Egypt.
00:07Majestic and mysterious shards of granite,
00:10rising from the heart of its greatest temples.
00:14Quarried from a single massive block of stone,
00:18some soar over 90 feet into the air.
00:21It's really the largest stone that ancient Egyptians ever worked with.
00:26What were these mighty needles for?
00:29And how did the ancient Egyptians raise them into the sky?
00:34Now, a team of archaeologists risks life and limb
00:38to rediscover the lost building techniques of the ancient Egyptians,
00:45and solve the mysteries of these enigmatic monuments.
00:52To unearth the answers,
00:54we'll deconstruct these towering stone Goliaths
00:59and reveal how ancient workers raised them.
01:04Why were Egypt's obelisks so important to the mighty pharaohs?
01:18Luxor, in the heart of southern Egypt.
01:22Two towering obelisks pierce the sky.
01:26They have stood here for over 3,000 years.
01:32Rare survivors of an ancient religion.
01:36The pharaohs erected dozens of these mystifying monuments,
01:40but many have fallen or been moved overseas.
01:46More now stand in distant cities like Paris,
01:49London, and New York,
01:53then remain in Egypt.
01:56These ancient stones are the most enigmatic of the pharaoh's monuments.
02:01But what were they for?
02:02And how were they built?
02:073,400 years ago,
02:10these two obelisks stood in one of Egypt's most important religious sites.
02:18Karnak, a huge temple complex built by generations of pharaohs.
02:28Its imposing gateways called pylons,
02:33and enormous covered halls,
02:37were dedicated to Egypt's chief god, Amun-Ra.
02:46At its center stood spectacular giant obelisks.
02:52How and why did the pharaohs build these extraordinary granite needles?
03:02This obelisk at Karnak is the tallest still standing in Egypt.
03:09The pharaoh Hatshepsut placed it here during the era of the New Kingdom.
03:17It is carved from a single block of granite,
03:20weighs over 300 tons,
03:22and soars 97 feet into the air.
03:30Adol Kalani is an Egyptian archaeologist.
03:33He wants to find out why this obelisk was built,
03:36and how Hatshepsut's workers raised it.
03:41Most of the pharaohs like to have obelisks detected to the Amun-Ra god.
03:46It's very, very special for them to have something like this.
03:50But why give a giant needle as a present to a god?
03:55In old times, the pharaoh believed that the whole world,
04:00it is completely covered with water.
04:02And when water sank down,
04:05there are small mountains start to appear.
04:09They call it Bin Bin.
04:11This mountain, in fact, is the top of the obelisk.
04:18These towering columns were a reminder of the creation of the first land,
04:22and the origins of the Egyptian people.
04:27They are among the most ancient Egyptian monuments.
04:32The pharaohs erected them in temples throughout their land
04:35to honor this idea of creation.
04:45They raised their largest and most impressive obelisks in Karnak.
04:52Six dominated the center of the temple complex.
04:56The tallest soared over 118 feet high.
05:00All were made from super tough granite to prevent them from snapping.
05:06The tips were covered in gold to reflect the sun's rays,
05:10and connect the earth and the heavens through the sun god Ra.
05:16But what huge resources did it take to move these monster blocks of stone?
05:21And how were they erected?
05:27Adil Kalani is preparing for a dangerous experiment
05:30that he hopes will finally solve these mysteries.
05:35He will use only the tools the ancient Egyptians had
05:38to move and raise this three-ton replica obelisk.
05:43He thinks this will reveal how they erected full-size ones thousands of years ago.
05:48His audacious plan relies on sand.
05:52It will be very simple, just building mud-brick room like this,
05:56and building ramps globing to the mud-brick room,
06:01and then fill the mud-brick room with sand,
06:04pulling the obelisk on the top of the mud-brick room,
06:06and then take the sand out,
06:08and then the obelisk will come down to get to the base.
06:12After that, raise it up with rope to the right position we needed.
06:20To remove the sand, Adil has installed two bricked-up windows on each side of the room.
06:27What we needed to just take all of these mud-bricks out and open this window.
06:33After we open the window, the sand will come immediately out.
06:38To strengthen the walls, Adil applies a plaster coating of mud.
06:43The room will need to hold 35 tons of sand.
06:47And if the walls collapse when he pours it in, the experiment will be over.
06:54Adil's next challenge is to build the giant ramp he will use to move the obelisk to the top of
07:00the mud-brick room.
07:02The pharaoh's huge workforce would have done this with simple tools.
07:08This is what the French Egyptians used to do.
07:10Just use a hundred or even a thousand of workmen doing this.
07:14But this is really taking a lot of time.
07:21To speed up the process, Adil brings in some heavy equipment.
07:31To build a ramp for a full-sized obelisk, it's been calculated that the ancient Egyptians would have needed over
07:37three million cubic feet of sand.
07:45With the ramp and the mud-brick room complete, Adil's next challenge will be to move the obelisk.
07:53You need to test it. This is our challenge.
07:57The replica obelisk is molded from concrete.
08:02The originals were carved from super-tough granite.
08:06How did the ancient Egyptians quarry and shape these extraordinary stones using only primitive tools?
08:15And how did Egypt's pharaohs move them hundreds of miles from the quarry to temples all over the country?
08:38The oldest stone monument standing in London, Paris, New York, and Istanbul
08:49all started life over 3,000 years ago here in this quarry at Aswan, southern Egypt.
08:59Its pink granite was perfect for building obelisks.
09:04The pharaohs considered these stone needles to be the ultimate offering to the gods
09:09and placed them in temples up and down the country.
09:15A giant, unfinished obelisk still remains in the Aswan quarry.
09:21Ancient workers abandoned it when the stone cracked.
09:30It took extraordinary skill to create the perfect obelisk.
09:35Craftsmen carved the base with great accuracy to ensure it would stand upright, without any cement.
09:44Each face was ground smooth, inscribed with intricate hieroglyphs, and painted in dazzling colors.
09:53Its pyramid-shaped tip was capped in real gold.
09:58It had to be perfect to do justice to the gods.
10:02But how did ancient workers carve these towering columns so precisely?
10:14Master stonemason Antoine Guerrique wants to find out how the Egyptians would have worked this extremely hard stone.
10:22As a stone mason, I'm very interested by knowing and understanding all the ancient construction techniques.
10:32Egypt's rulers usually erected obelisks in pairs.
10:37Next to the pharaoh Hatshepsut's surviving obelisk lies its twin.
10:44Workers carved both from single blocks of Aswan pink granite in about 1470 BC.
10:53Antoine investigates how they got them out of the ground and carved them.
10:58It's completely flat and smooth.
11:02It's so accurate. It's amazing.
11:07How did ancient workers cut through this tough granite rock?
11:15At that time, the Egyptians were unable to smelt iron.
11:20They depended on bronze and copper tools.
11:24These worked well on soft rocks like sandstone and limestone.
11:31But they couldn't cope with much harder granite.
11:38So as you can see, you know, copper tools on granite doesn't work at all.
11:43We are just destroying our chisel, so it doesn't work.
11:49Antoine thinks that instead of chisels, they used a stone even harder than granite.
11:55Dolarite.
11:57But would this have worked?
12:00To find out, Antoine attempts to cut a test area in a granite block.
12:05Just by heating like this, we are exploding the granite as powder, in fact.
12:14It's very hard work.
12:16But there is no other solution, in fact, to cut and to cut hard stone in this time.
12:25To work out how long it would take to extract an obelisk from a quarry, Antoine pounds the granite for
12:32an hour.
12:35So in this experiment, I did 20 centimeters square in one hour.
12:42So I get down about five millimeters.
12:45That means a simple worker in seven months could achieve one qubit metal.
12:51One cubic meter is about 35 cubic feet.
12:55At that rate, 500 workers could extract an obelisk in seven months.
13:02With this technique, you can quarry out an obelisk.
13:09Antoine has shown that Dolarite stones are tough enough to carve granite.
13:14But how did ancient workers make the sides of the obelisk so smooth?
13:22Antoine thinks they did it by grinding.
13:25Antoine, we find everywhere a flat grinding stone.
13:30It's completely flat and smooth.
13:33As you can see, without any sand, it's just slimy.
13:39It doesn't work at all.
13:41But on the sand, we start to see white powder from the granite.
13:55But the abrasive sand is even more effective when mixed with water.
14:05You can see the results after one hour.
14:09So now it's quite smooth.
14:13We've been down about three millimeters to get this smooth surface.
14:19That means that perhaps with 100, 200 people working on the same surface, for example, on a huge obelisk, they
14:26could achieve the complete grinding and polishing on one face perhaps in one or two weeks, which is pretty fast.
14:35But the biggest mystery is how the Egyptians would have carved the detailed inscriptions.
14:42On the Pharaoh Hatshepsut's obelisk, the hieroglyphs describe how she made it with a loving heart for her father, the
14:50god Amun-Ra.
14:51The craftsmanship is sublime.
14:58Antoine is setting up an experiment to see if copper tools combined with sand can grind away granite precisely enough
15:06to make such fine carvings.
15:10So now we start the drilling.
15:13So we use water and sand.
15:23And just by rotating the tube, it starts to grind the granite.
15:30You can hear the sand.
15:40So now we can check how deep it has been now, after 10 minutes.
15:47So as you can see here, we have the beginning of the drilling.
15:51And after about 10, 15 minutes, we got something like three millimeters, which is quite efficient, in fact.
15:58It works well.
16:02Antoine thinks ancient workers would have carved these inscriptions by first hammering the granite with stone punches to make small
16:10grooves.
16:11Then they cut out the hieroglyphs with copper tools and an abrasive.
16:19Using resources they had in abundance, labor, and sand, the ancient Egyptians quarried, polished, and carved their imposing obelisks.
16:30Creating masterpieces that people would continue to marvel at for centuries.
16:37But this was just the beginning of a phenomenally expensive and dangerous operation.
16:43Next, the pharaohs had to move the obelisks to the temples, some hundreds of miles away.
16:51This required extraordinary ingenuity and huge resources.
16:58Investigators believe the Egyptians dug canals deep into the landscape, so water from the Nile would flow towards the quarry.
17:08The obelisk was suspended over the water.
17:11Then a boat was weighed down with stones, so that when it was empty, it would pick up the obelisk
17:17and carry it down the Nile.
17:22But Egypt's great river would only take it part of the way.
17:28To move the obelisk from the ship to the temple, they needed to carry it over land, without damaging the
17:35precious stone.
17:37What was their ingenious solution?
17:40Any method of transporting it would have required vast amounts of labor.
17:46How could the pharaohs feed this huge workforce in an arid desert that receives only a fraction of an inch
17:53of rain per year?
18:10For over a thousand years, Egypt's pharaohs erected extraordinary giant obelisks outside their temples.
18:18These were the most precious offerings to their gods.
18:23The tallest tower over 98 feet high, and are among the largest stones ever quarried.
18:31But how did ancient workers move and raise these giant monoliths?
18:39In Aswan, archaeologist Adil Kalani is conducting a dangerous and pioneering experiment to find out.
18:49So far, he has constructed a mud brick room and a long ramp.
18:54His plan is to haul the obelisk to the top of the room, fill the room with sand, and then
19:01slowly release the sand to tilt the obelisk into position.
19:06But first, he must pull it up the ramp.
19:10Weighing three tons, it is heavy enough to cause serious injury if the experiment goes wrong.
19:19To reduce friction, Adil lays a wooden track for rollers to carry the obelisk.
19:25It's a method based on evidence from excavations.
19:29We did find some fragments of rollers like this.
19:32They use local wood, like acacia, good for this kind of hard work.
19:38Because this is dangerous, the team will use modern rope.
19:42Ancient workers would have had a similar hauling line made from reeds.
19:49Adil has calculated that he will need 30 people to pull the obelisk up the slope.
19:56But first, he tests it on level ground.
19:59One, two, three. One, one, one, one, one.
20:06We tested the system of rollers and it's moving very fast, more than what we expected.
20:12But there's a problem.
20:14The team is soon struggling to keep the long, thin needle on course.
20:19If you are not careful with this, it might go away from the track.
20:23So we make sure that each time we correct the orientation of the obelisk
20:28to be in right position to the ramp.
20:33The team shows it can move the obelisk on level ground.
20:38How will they fare on the ramp?
20:41One, two, three.
20:54Little by little, it rolls up the slope.
21:00It's amazing. I think they can definitely move obelisk in this kind of way.
21:04Because there are no other way to do this kind of very, very heavy obelisk like this.
21:11It's a titanic battle to haul the obelisk to the top of the ramp.
21:18Atal believes that to move a full-sized 320-ton obelisk the same way would require about 1,000 workers.
21:32At last, they reach the top. The first stage is complete.
21:36But now they must try to move the obelisk into position.
21:42So the next step is to prepare the mud brick room.
21:45We have to wait a little bit until we fill the mud brick room with sand.
21:53But will the room's thin walls be strong enough to hold 35 tons of sand?
22:05As the level of sand approaches the top, Atal's carefully laid plan starts to fall apart.
22:16It looks like the mud brick room could collapse.
22:21We have a problem here.
22:23As you can see the cracking in the mud brick rooms.
22:27I think when the loaders started to put the sand inside the room,
22:33it was not strong enough to receive this kind of heavy sand package from the loader.
22:41To prevent the walls falling down, Atal quickly orders the loader to pile sand on the outside.
22:50He improvises extra support.
22:53We will try to tie it with these wooden beams and hopefully it will work.
23:01We need to be sure that everything is tied all together.
23:07Atal hopes this frame will enable the walls to support the extra weight of the obelisk.
23:13He's about to find out.
23:27And now we put it more and less in the right position we needed.
23:32The mud brick walls have taken the strain, for the moment.
23:36But there's a problem.
23:38The obelisk's weight has created more cracks.
23:41The safety engineer is not happy.
23:45I'm concerned about safety here.
23:47I need some kind of plan.
23:48When the wall collapses, no one gets hurt.
23:50What is the plan for if it collapses?
23:52We have to build another one.
23:55In a makeshift attempt to prevent the mud brick room from collapsing,
24:00Atal adds more timber to support its walls.
24:03But will it be enough?
24:06And in a desert country with almost no rain,
24:10how did they grow the food to feed the vast army of men it took to create these stone giants?
24:32The towering obelisks of Luxor, southern Egypt.
24:39The pharaohs erected these ancient granite skyscrapers nearly three and a half thousand years ago.
24:48This was the era of the New Kingdom.
24:51A golden age when the country prospered after driving out invaders.
24:58The greatest obelisks were built during this time.
25:05These were taller, heavier and more finely carved than any that had gone before.
25:12To quarry and raise these mighty monoliths, thousands of people had to work for months on end.
25:22But most of Egypt is in the Sahara.
25:25Its climate is hostile.
25:27Rainfall is less than a fraction of an inch per year.
25:32So how did the pharaohs feed this vast army of workers?
25:40Half a mile away from Karnak's obelisks, at the Temple of Mut, excavators find new clues that could reveal the
25:47source of ancient Egypt's vital food supply.
25:51We have this layer of pottery.
25:53You can hear it when I hit it.
25:55And it's lying actually on this surface.
26:06This circle of mud bricks shows that this was once a granary.
26:11A storage silo for grain.
26:14During the harvest, workers would fill it with wheat or barley.
26:20To provide food throughout the year.
26:31It was accessed using steps that led up to a hatch.
26:37But how many people could these granaries feed?
26:41And where did this grain come from?
26:50American archaeologist Betsy Bryan thinks this excavation could reveal the answers.
26:58All of this area that we're working in is an industrial area.
27:02And so they were making bread, they were making beer.
27:06Granaries were essential for running the economy.
27:09There were no coins or money in the time of the New Kingdom.
27:13Instead, workers were paid in grain.
27:16So how many workers could this granary support?
27:23Betsy takes measurements to find out.
27:27So these granaries, they're mostly about 3.8 meters in diameter.
27:34We've unearthed at least six, and we have indications that they actually have the ability to have supported up to
27:424,000 people with the amount of grain being stored.
27:47How could they grow so much grain in these arid conditions?
27:53In Egypt's desert climate, the amount of land available for growing wheat and barley was limited.
28:01Most of the fields of Egypt were actually planted within 2 miles of the Nile River itself, in an area
28:09that was a flood plain.
28:11More than 1,000 miles of it along the Nile.
28:16And so the grain would be grown, it would be harvested and put onto large barges, and the barges would
28:24be brought upstream and then unloaded in large amounts and stored in granaries.
28:34When the Nile flooded, it would fertilize the nearby land, meaning Egyptian farmers could harvest a rich crop of wheat
28:41and barley.
28:43The state and religious temples controlled the grain, and used it to pay the obelisk workers.
28:55Thanks to the Nile, the pharaohs had plenty of food to feed the huge workforce needed to erect the obelisks.
29:04But how did ancient builders tilt them into position?
29:09And why did so many of Egypt's sacred columns end up in the major cities of distant countries?
29:333,400 years ago, the pharaoh Hatshepsut erected this 320-ton obelisk as a gift to the god Amun-Ra.
29:44But how did ancient workers raise it into position?
29:50In Aswan, Adil Kalani is undertaking a huge and dangerous experiment to find out.
29:57By releasing sand from under a replica obelisk, he plans to tilt it upright inside a mud-brick room.
30:06But cracks in the walls threaten to derail the operation.
30:10Safety engineer Rami Aransa is worried the mud-brick room could collapse.
30:17I don't want to surprise. It could surprise us.
30:20Because I really don't think that support system, I'm not 100% sure that it would hold it.
30:27We tied it from all sides. As you can see, it's protected from all sides, and I think it would
30:34be holding it.
30:41With workers watching the walls to check that no more cracks appear, Adil begins the raising operation.
30:49What we are going to do right now, actually, is to just break the windows to take the sand out.
30:55Workers pull out the bricks from two of the windows of the mud-brick room to start removing the sand.
31:02This should lower the base of the obelisk and pivot it until it's nearly upright.
31:09From there, the team should be able to pull it vertical.
31:15Adil must carefully control the release of the sand to maneuver the obelisk accurately onto the plinth below.
31:24It is really very, very difficult to do the balance between taking the sand from both windows at the same
31:29time.
31:30If you take it more from one side, that might cause a lot of problems for, you know, going to
31:36completely wrong direction.
31:40Little by little, the workers remove the sand from the sandbox.
32:00The obelisk is only moving very slowly, so Adil decides to speed up the process.
32:08We will open the rest of the windows to take a little bit more sand.
32:13The team pulls out more mud bricks to create another two openings.
32:25The obelisk is moving faster, but there's a hitch. It's not going in the right direction.
32:33It's come too far to the front. It should be backed up a little bit.
32:38Instead of pivoting and dropping, the obelisk is sliding across the mud brick room.
32:45It's not where we want to be. It's a problem.
32:50It's a serious setback. If the obelisk continues to slide, it will end up lying at an angle that will
32:57make it impossible to pull upright.
33:11To get the obelisk as vertical as possible, Adil shovels away the sand from immediately under the center of it.
33:20But supported only at its base, the obelisk makes a sudden move.
33:30Safety engineer Ramy calls a halt.
33:35It's not safe. I had to stop it. So at that point, we're going to have to break the rest
33:39of the window.
33:40It's safer that way. I just can't let them keep because it could fall over either side.
33:47From outside the room, the team carefully removes sand until the obelisk settles into a stable position.
33:58It takes three hours to maneuver the obelisk within one foot of the plinth.
34:05To raise Hatshepsut's 97 foot tall obelisk the same way, Adil believes ancient workers would have needed a mud brick
34:13room 98 feet high.
34:15And around a month to take away the sand.
34:21Now we reach the base of the obelisk and it was successful. We will try to erect it.
34:29Now Adil and the team must pull the obelisk upright.
34:34It's a tricky operation. If they use too much force, they could tip the obelisk right over.
34:55After a nerve-jangling wobble, the obelisk settles on its base.
35:04We successfully erected like this and it was a very interesting moment.
35:14When the obelisk started to go and back a little bit, it was really a very, very scary moment.
35:20But science forgot that it's back to the right position.
35:25Adil and the team have successfully shown that the sandbox method works.
35:31This is the perfect technique for standing the obelisk.
35:34Even if it is taller and has more weight, it will work very well.
35:38This is a really clear answer for us how the Egyptians do it.
35:47The obelisks were the crowning glory of the new kingdom pharaohs.
35:52An astonishing achievement that inspired awe and wonder.
35:58But of the dozens of obelisks the pharaohs raised,
36:02more now stand in cities of other countries than remain in Egypt's temples.
36:10So how did so many obelisks end up in distant lands?
36:31From these quarries in Aswan, southern Egypt, the pharaohs extracted dozens of granite obelisks
36:38and erected them in temples across the country.
36:46Today, fewer than 10 of these large stone needles remain standing in Egypt.
36:52But elsewhere in the world, you can see over 20.
36:59How did so many obelisks end up overseas?
37:05The temple of Karnak once boasted at least 13 obelisks, including some of the most impressive ever raised.
37:13The tallest was over 118 feet high.
37:18Today, in the center of the temple, only two remain.
37:23In their shadow, archaeologist Benjamin Durand unearths new evidence that could reveal what happened to some of the missing obelisks.
37:37At the temple of Ptah, just 600 feet from the remaining ones, Benjamin uncovers a clue.
37:46So we found three coins.
37:48To have this kind of evidence is always very interesting for us.
37:51But as we can see, the surface of the coin is pretty much corroded.
37:59In the laboratory, restoration expert Lucy Antoine attempts to reveal any details in the coins that will shed light on
38:08what happened to the temple complex of Karnak and its missing obelisks.
38:12We have to put the coin on the chemical bath to dissolve the corrosion.
38:19This softens the outer corrosive layer, enabling Lucy to clean it away with a micromotor.
38:36We're pretty lucky because it is well preserved. We can see all the details.
38:40The cleaned surface reveals this coin's origins.
38:46So this coin is showing the face of Constantine.
38:50It's a Roman emperor.
38:52And among this empire was, of course, Egypt.
38:56Constantine is well known as the first Christian emperor.
39:02Constantine's name on these coins shows that the great temple and its obelisks had fallen to the Romans.
39:10In 30 BC, the last pharaoh, Cleopatra, committed suicide, and the powerful Roman Empire took control of Egypt.
39:22In the center of Karnak, Antoine Garrick is only now repairing the damage the Romans caused when they looted the
39:30temple complex.
39:33We are finishing the rebuilding of a wall which has been dismantled by Romans more than 1,700 years ago.
39:43They're dismantling two parts of those walls to get through the courtyard with a nobelisk, a huge one.
39:50Whenever the Romans invaded a country, they liked to seize its monuments and re-erect them in their capital city
39:57as a dramatic display of their might and power.
40:03Around 335 AD, Constantine I ordered the removal of two of Karnak's obelisks.
40:13The Romans shipped one to Constantinople, now Istanbul.
40:20They transported the other to Rome.
40:24At 105 feet tall, it's the largest ancient obelisk in the world.
40:31The Romans filled their city with eight large and 42 small Egyptian obelisks.
40:40Much later, in the 1800s, after diplomatic requests, Egypt's Ottoman rulers gave away three more of these giant stones, nicknamed
40:49Cleopatra's Needles.
40:56The first was shipped to Paris and re-erected in the Place de la Concorde.
41:01The second was placed in London, beside the Thames.
41:05And the last was raised in New York's Central Park.
41:10Here they still stand, majestic reminders of the extraordinary society that built them.
41:20To the ancient Egyptians, these sky-piercing columns played a vital role in their religion.
41:29They connected the earth and the heavens through the sun god, Ra.
41:34And now, through archaeology and experiment, they are revealing their final secrets.
41:43The great civilization that created these sublime spires of granite has long since disappeared.
41:51But through these extraordinary monuments, it will continue to be remembered.
41:59To the throne and the
42:26TRIBO
42:26To the throne and the
42:27You
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