1 00:00:01,735 --> 00:00:04,071 How could the ancients build colossal 2 00:00:04,071 --> 00:00:05,639 structures in less time than we 3 00:00:05,738 --> 00:00:09,675 can construct the biggest buildings of today? 4 00:00:09,742 --> 00:00:13,013 How could the ancient Egyptians produce thousands of chariots 5 00:00:13,080 --> 00:00:16,882 with assembly line precision? 6 00:00:16,950 --> 00:00:20,821 Why did the Romans create a massive underground industrial 7 00:00:20,887 --> 00:00:23,889 hell where thousands of slaves 8 00:00:23,890 --> 00:00:27,961 never saw the light of day? 9 00:00:28,094 --> 00:00:31,632 Monuments more colossal than our own, ancient 10 00:00:31,699 --> 00:00:36,035 super weapons as mighty as today's, technology so precise, 11 00:00:36,102 --> 00:00:40,039 it defies reinvention. 12 00:00:40,106 --> 00:00:43,043 The ancient world was not primitive. 13 00:00:43,109 --> 00:00:45,044 Their marvels are so advanced, 14 00:00:45,111 --> 00:00:48,447 we still use them now. 15 00:00:48,514 --> 00:00:50,017 Travel to a world closer than 16 00:00:50,084 --> 00:00:52,653 we imagine, an ancient age 17 00:00:52,720 --> 00:00:55,022 where nothing was impossible. 18 00:01:00,561 --> 00:01:03,696 The biggest builds of today are the result of mammoth 19 00:01:03,696 --> 00:01:05,765 engineering projects, huge 20 00:01:05,833 --> 00:01:08,735 structures that define the modern era. 21 00:01:08,803 --> 00:01:12,205 But who were the greatest engineers of all time? 22 00:01:12,273 --> 00:01:15,576 Could there have been building projects just as impressive in 23 00:01:15,642 --> 00:01:18,311 ancient times? 24 00:01:18,378 --> 00:01:21,714 The Romans were not only the biggest and strongest power of 25 00:01:21,782 --> 00:01:24,718 the ancient world, but they were 26 00:01:24,785 --> 00:01:28,788 also the most technologically advanced. 27 00:01:28,856 --> 00:01:32,793 They made amazing buildings and military machines. 28 00:01:32,859 --> 00:01:36,262 They were so ahead of their time, that it's only recently 29 00:01:36,330 --> 00:01:41,002 that modern engineers have been able to replicate their techniques. 30 00:01:41,202 --> 00:01:44,604 And one of the Romans' most incredible discoveries? 31 00:01:44,672 --> 00:01:46,206 Concrete. 32 00:01:46,273 --> 00:01:50,276 It's only in the last 100 years or so that concrete has come to 33 00:01:50,344 --> 00:01:53,814 play such a large part in our architecture. 34 00:01:53,880 --> 00:01:56,516 But it's actually a rediscovery. 35 00:01:56,583 --> 00:01:58,484 Amazingly, the Romans were using 36 00:01:58,552 --> 00:02:02,822 it for their biggest builds over 2,000 years ago. 37 00:02:02,889 --> 00:02:05,692 The science of concrete was perfected by the Romans 38 00:02:05,758 --> 00:02:07,260 thousands of years ago. 39 00:02:07,327 --> 00:02:12,266 And when the Roman civilization fell, that science was lost. 40 00:02:12,332 --> 00:02:14,835 And the most amazing example of this Roman 41 00:02:14,902 --> 00:02:16,837 engineering miracle is to be 42 00:02:16,903 --> 00:02:22,843 found here, at Caesarea, on the coast of present-day Israel. 43 00:02:22,909 --> 00:02:25,445 Unbelievably, they built a huge 44 00:02:25,512 --> 00:02:29,116 harbor made of concrete, and it was one of the biggest 45 00:02:29,182 --> 00:02:31,851 artificial ports in the ancient world. 46 00:02:31,919 --> 00:02:35,856 Imagine how our cities and ports might have developed if this 47 00:02:35,922 --> 00:02:39,659 knowledge hadn't been lost. 48 00:02:39,726 --> 00:02:41,662 It was another 2,000 years 49 00:02:41,729 --> 00:02:43,464 before mankind could replicate 50 00:02:43,531 --> 00:02:45,432 this technology. 51 00:02:45,498 --> 00:02:46,866 When the technology was 52 00:02:46,933 --> 00:02:48,801 rediscovered, it essentially 53 00:02:48,868 --> 00:02:50,437 shaped the modern world. 54 00:02:50,504 --> 00:02:54,341 Everything around us relies upon the presence of concrete. 55 00:02:54,408 --> 00:02:57,878 But what's so special about concrete? 56 00:02:57,944 --> 00:03:01,314 It can be shaped and molded. 57 00:03:01,381 --> 00:03:06,152 With concrete, the Romans could make arches, vaults and domes. 58 00:03:06,219 --> 00:03:08,354 This was revolutionary. 59 00:03:08,421 --> 00:03:10,891 If you imagine times before concrete, you're relatively 60 00:03:10,957 --> 00:03:14,327 limited to what it was you could dream up, but then the minute 61 00:03:14,395 --> 00:03:18,231 that you could create these manmade stones in essentially 62 00:03:18,299 --> 00:03:22,368 any shape you wanted, architects were they were free to dream. 63 00:03:22,436 --> 00:03:26,439 They were liberated, and they did dream. 64 00:03:26,506 --> 00:03:28,242 And at Caesarea, 65 00:03:28,308 --> 00:03:34,314 they dreamt the impossible using concrete underwater. 66 00:03:34,380 --> 00:03:38,318 This was something extraordinary. 67 00:03:38,385 --> 00:03:40,454 In modern times, underwater 68 00:03:40,521 --> 00:03:44,190 concrete has only been used for about 150 years. 69 00:03:44,258 --> 00:03:48,195 But the Romans were using it 2,000 years ago. 70 00:03:48,261 --> 00:03:52,199 This sounds impossible, but here at Caesarea, the Romans made the 71 00:03:52,266 --> 00:03:54,635 impossible possible. 72 00:03:54,701 --> 00:03:57,803 I'm standing amidst the ruins of the impressive artificial 73 00:03:57,871 --> 00:04:00,540 harbor in Caesarea. 74 00:04:00,607 --> 00:04:07,813 This would have been an incredible sight in the ancient world. 75 00:04:08,015 --> 00:04:10,950 The harbor was certainly an engineering marvel, 76 00:04:11,017 --> 00:04:14,921 over a million cubic feet of concrete embedded in the sea. 77 00:04:17,491 --> 00:04:21,494 Just the thought of building a manmade harbor was a sign of the 78 00:04:21,495 --> 00:04:23,797 audacity of the Romans, and then 79 00:04:23,863 --> 00:04:25,666 the decision to use concrete was 80 00:04:25,733 --> 00:04:28,569 even more astonishing. 81 00:04:28,635 --> 00:04:30,970 And the man behind it? 82 00:04:31,037 --> 00:04:34,575 Herod, the Roman's puppet king of Judea. 83 00:04:34,642 --> 00:04:37,544 He's often thought of as an evil tyrant. 84 00:04:37,611 --> 00:04:40,781 But because he was in league with the Romans, he was able to 85 00:04:40,847 --> 00:04:43,984 commission some of the greatest megabuilds. 86 00:04:44,051 --> 00:04:46,653 King Herod needed a large harbor. 87 00:04:46,719 --> 00:04:49,555 There were no natural places to anchor ships. 88 00:04:49,623 --> 00:04:52,993 He decided to build one from scratch. 89 00:04:53,060 --> 00:04:56,996 The harbor itself was unbelievably huge, big. 90 00:04:57,063 --> 00:05:00,833 Nobody could see such a big structure worldwide. 91 00:05:01,899 --> 00:05:04,938 It was the largest structure on earth at the time. 92 00:05:05,005 --> 00:05:11,010 90,000 square yards that's a huge area. 93 00:05:11,077 --> 00:05:14,313 The port extends on either side of where I'm standing to 94 00:05:14,380 --> 00:05:18,351 the south over 1,500 feet long. 95 00:05:18,419 --> 00:05:22,022 On the northern side, about 1,000 feet long. 96 00:05:22,089 --> 00:05:27,027 You have to think of about 40 acres or 30 football fields are 97 00:05:27,094 --> 00:05:31,497 comprised within the two arms projecting forward. 98 00:05:31,565 --> 00:05:36,837 He created water-breaks that was 180 feet wide, huge 99 00:05:36,904 --> 00:05:39,505 you could have a highway on top of it. 100 00:05:39,573 --> 00:05:47,481 It extended deeply to the sea almost half a mile into the sea. 101 00:05:49,049 --> 00:05:52,652 Herod wanted to build a huge harbor to rival any 102 00:05:52,719 --> 00:05:55,354 in the world, and that's despite the lack of a good 103 00:05:55,421 --> 00:05:58,058 natural harbor at this site. 104 00:05:58,125 --> 00:05:59,892 This was because he wanted his 105 00:05:59,960 --> 00:06:02,061 province of Judea to be the main 106 00:06:02,128 --> 00:06:04,597 trading route for east to west. 107 00:06:04,664 --> 00:06:08,802 His incredible harbor could accommodate 300 ships. 108 00:06:08,868 --> 00:06:14,541 It dwarfed anything found here before or since. 109 00:06:14,608 --> 00:06:16,076 See part of the modern port over here. 110 00:06:16,142 --> 00:06:21,081 The actual breakwater of the port of Caesarea is underneath, 111 00:06:21,147 --> 00:06:24,750 and it's sunken down about 5 meters beneath the surface. 112 00:06:24,818 --> 00:06:29,955 But it extended twice the length out into the sea. 113 00:06:30,022 --> 00:06:32,625 The concrete harbor was so impressive that king 114 00:06:32,693 --> 00:06:36,096 Herod built a new palace for himself on the waterfront. 115 00:06:36,162 --> 00:06:40,400 And the port became the catalyst for a great, trading city and 116 00:06:40,467 --> 00:06:44,104 a new capital for Judea. 117 00:06:44,171 --> 00:06:47,440 This port was a commercial center, a hub. 118 00:06:47,508 --> 00:06:48,842 There's a massive market in the 119 00:06:48,909 --> 00:06:51,111 Western half of the mediterranean. 120 00:06:51,178 --> 00:06:53,380 The Roman senators, they want 121 00:06:53,447 --> 00:06:56,449 the goods from the middle east and from the orient. 122 00:06:56,517 --> 00:06:57,984 This became one of the key 123 00:06:58,051 --> 00:07:00,087 harbors that brought those goods 124 00:07:00,154 --> 00:07:02,456 from east to west. 125 00:07:02,522 --> 00:07:05,991 But how did the Romans build this harbor? 126 00:07:06,058 --> 00:07:07,827 What was the magic ingredient 127 00:07:07,895 --> 00:07:10,597 that they used to make the concrete set? 128 00:07:10,664 --> 00:07:14,868 And how did they lay concrete underwater? 129 00:07:14,935 --> 00:07:20,440 It's only recently that we have uncovered the truth. 130 00:07:20,507 --> 00:07:23,409 At this concrete factory in Austin, Texas, they have the 131 00:07:23,476 --> 00:07:25,145 ingredients prepared. 132 00:07:25,212 --> 00:07:26,479 There are seven ingredients 133 00:07:26,546 --> 00:07:29,549 in marine mix concrete 134 00:07:29,616 --> 00:07:33,152 quicklime, clay, seawater, sand, 135 00:07:33,219 --> 00:07:36,455 fly-ash, large aggregates, and 136 00:07:36,522 --> 00:07:40,726 animal blood, in this case, pig blood. 137 00:07:40,794 --> 00:07:46,598 One theory is that blood was used to strengthen the mixture. 138 00:07:46,799 --> 00:07:52,171 But the key to underwater setting lay elsewhere. 139 00:07:52,238 --> 00:07:55,508 They'd developed a kind of mortar that had extraordinarily 140 00:07:55,575 --> 00:07:59,044 good lime in it, and that made it strong to begin with, but the 141 00:07:59,111 --> 00:08:02,448 real key is the chemical reaction that happened when they 142 00:08:02,515 --> 00:08:08,053 added pozzolana sand to their mortar. 143 00:08:08,121 --> 00:08:12,191 This special kind of sand came from volcanic ash. 144 00:08:12,258 --> 00:08:16,662 It made the concrete so durable, it could harden underwater. 145 00:08:16,729 --> 00:08:20,534 Luckily, thanks to mount vesuvius in Italy, the Romans 146 00:08:20,601 --> 00:08:25,939 could find this sand in abundance. 147 00:08:26,005 --> 00:08:27,808 The fact that mount vesuvius was 148 00:08:27,875 --> 00:08:30,043 over 1,200 miles away wasn't 149 00:08:30,109 --> 00:08:32,678 going to stop them. 150 00:08:32,746 --> 00:08:37,617 So they have to ship over this volcanic sand in enormous amounts. 151 00:08:37,818 --> 00:08:42,222 We're talking about 44 ships with a 400-ton capacity. 152 00:08:42,289 --> 00:08:46,092 Without that, this artificial harbor could not have been built. 153 00:08:46,293 --> 00:08:50,697 So it's something that the Romans develop and perfect, and 154 00:08:50,764 --> 00:08:52,698 it allows them to pour this and 155 00:08:52,765 --> 00:08:56,702 have it harden in the saltwater. 156 00:08:56,770 --> 00:08:59,239 Marine concrete hasn't been made in this way 157 00:08:59,305 --> 00:09:02,708 since Roman times. 158 00:09:02,775 --> 00:09:06,812 Is it possible that it can be re-created today? 159 00:09:06,880 --> 00:09:09,114 We work with concrete all the time. 160 00:09:09,182 --> 00:09:13,587 We're going to try today to re-create ancient marine 161 00:09:13,654 --> 00:09:18,258 concrete like used at the ancient harbor of Caesarea. 162 00:09:18,324 --> 00:09:21,595 For the Romans to discover 2,000 years ago that 163 00:09:21,661 --> 00:09:25,198 volcanic ash would have this effect was an enormous 164 00:09:25,265 --> 00:09:26,967 technological leap. 165 00:09:27,034 --> 00:09:30,270 And this was done on an industrial scale. 166 00:09:30,337 --> 00:09:31,737 Hundreds of slaves would have 167 00:09:31,804 --> 00:09:34,140 been used to carry, mix and pour 168 00:09:34,207 --> 00:09:35,575 the materials. 169 00:09:35,641 --> 00:09:38,145 It must have been a massive operation. 170 00:09:41,682 --> 00:09:46,086 This ancient concrete mix is going underwater. 171 00:09:46,086 --> 00:09:50,289 It will be ready for testing in 30 days. 172 00:09:50,356 --> 00:09:51,957 We're going to find out if this 173 00:09:52,025 --> 00:09:54,093 ancient concrete recipe really 174 00:09:54,160 --> 00:09:59,665 works. 175 00:10:18,432 --> 00:10:21,836 The ancient empires of the mediterranean depended on 176 00:10:21,902 --> 00:10:24,239 sea power for military dominance 177 00:10:24,306 --> 00:10:26,773 and for trade. 178 00:10:26,840 --> 00:10:28,710 The Romans were no different. 179 00:10:28,777 --> 00:10:30,845 In fact, they always took things 180 00:10:30,912 --> 00:10:33,248 to another level. 181 00:10:33,315 --> 00:10:35,650 They had to have the best ships, 182 00:10:35,716 --> 00:10:37,384 the best crews, and to go with 183 00:10:37,451 --> 00:10:41,922 them, the greatest, most up-to-date ports. 184 00:10:41,989 --> 00:10:44,258 It's not so different today. 185 00:10:44,325 --> 00:10:47,595 The major cities of the world are ports. 186 00:10:47,662 --> 00:10:50,364 90% of all the world's trade is 187 00:10:50,431 --> 00:10:54,268 still transported by sea. 188 00:10:54,335 --> 00:10:56,037 In ancient times, great cities 189 00:10:56,104 --> 00:10:58,273 such as carthage and Alexandria 190 00:10:58,340 --> 00:11:00,274 grew up around their ports. 191 00:11:00,341 --> 00:11:01,775 But the Romans were able to do 192 00:11:01,843 --> 00:11:04,678 what for everyone else was impossible. 193 00:11:04,745 --> 00:11:07,949 They could build a port like no other. 194 00:11:08,016 --> 00:11:12,287 It was built bigger, and it was built to last. 195 00:11:12,354 --> 00:11:15,890 And at Caesarea today, the massive 2,000-year-old concrete 196 00:11:15,956 --> 00:11:18,426 jetties can still be seen just 197 00:11:18,493 --> 00:11:21,528 under the water. 198 00:11:21,595 --> 00:11:24,666 As a diver, what you see just below the surface of the water 199 00:11:24,733 --> 00:11:26,034 is huge constructions. 200 00:11:26,100 --> 00:11:28,835 The poured concrete is intact, 201 00:11:28,902 --> 00:11:32,040 and as you swim along you'll see actual 202 00:11:32,106 --> 00:11:35,542 the imprints of the wooden framework into which the 203 00:11:35,609 --> 00:11:39,681 concrete was poured. 204 00:11:39,748 --> 00:11:41,316 This is remarkable. 205 00:11:41,383 --> 00:11:44,418 This concrete is 2,000 years 206 00:11:44,485 --> 00:11:47,955 old, and it's still intact on the seabed. 207 00:11:48,022 --> 00:11:49,324 How did the Romans lay this 208 00:11:49,391 --> 00:11:53,795 concrete underwater? 209 00:11:53,861 --> 00:11:58,598 It's an engineering marvel. 210 00:11:58,666 --> 00:12:02,336 Specially made wooden barges were partly filled with concrete 211 00:12:02,403 --> 00:12:07,608 and floated into position, then anchored. 212 00:12:07,675 --> 00:12:11,745 More concrete was then poured in. 213 00:12:11,812 --> 00:12:14,348 So you set those up, you pour 214 00:12:14,416 --> 00:12:17,352 in the concrete, and as it settles and hardens and 215 00:12:17,418 --> 00:12:20,354 solidifies you can sink it down to the bottom where it would 216 00:12:20,422 --> 00:12:23,358 harden and be able to withstand the force of the sea, and 217 00:12:23,425 --> 00:12:25,759 they're gonna build these in sections. 218 00:12:25,826 --> 00:12:29,429 It's just a massive enterprise. 219 00:12:29,497 --> 00:12:32,367 This process, repeated again and again, 220 00:12:32,433 --> 00:12:35,836 eventually led to the massive concrete jetties rising from the 221 00:12:35,903 --> 00:12:40,774 sea. 222 00:12:40,841 --> 00:12:44,378 And the giant jetties would probably still be in use today 223 00:12:44,446 --> 00:12:48,515 if they hadn't been built on a seismic fault. 224 00:12:48,582 --> 00:12:54,021 Over the years, earthquakes have taken their toll. 225 00:12:54,088 --> 00:12:57,758 Still, the concrete has survived. 226 00:12:57,825 --> 00:13:00,394 Modern concrete routinely shows 227 00:13:00,461 --> 00:13:04,532 signs of degradation after just 50 years. 228 00:13:04,599 --> 00:13:07,534 The strength of concrete can be tested. 229 00:13:07,601 --> 00:13:09,069 And at this engineering company 230 00:13:09,137 --> 00:13:11,037 in Austin, Texas, they have a 231 00:13:11,104 --> 00:13:13,407 special machine to do just that. 232 00:13:13,475 --> 00:13:15,909 Basically what we do is we put a concrete cylinder in the 233 00:13:15,976 --> 00:13:19,413 press and apply a load, and see how much compressive force it 234 00:13:19,480 --> 00:13:23,417 can take. 235 00:13:23,484 --> 00:13:26,854 New concrete like this holds out well. 236 00:13:31,893 --> 00:13:33,494 If they had a similar cylinder 237 00:13:33,494 --> 00:13:35,496 of Roman concrete, they could 238 00:13:35,497 --> 00:13:40,535 precisely measure its strength. 239 00:13:40,601 --> 00:13:42,836 In the nearby concrete factory, 240 00:13:42,903 --> 00:13:48,442 a mix of Roman concrete has been left to harden. 241 00:13:48,509 --> 00:13:51,446 And now, the time has come. 242 00:13:51,513 --> 00:13:53,848 How has the special Roman mix of 243 00:13:53,915 --> 00:13:59,086 underwater concrete fared? 244 00:13:59,152 --> 00:14:01,455 Well, to me this is amazing. 245 00:14:01,523 --> 00:14:03,925 This block of marine mix 246 00:14:03,992 --> 00:14:05,660 concrete actually formed. 247 00:14:05,726 --> 00:14:07,861 I didn't think it was going to form like this. 248 00:14:07,928 --> 00:14:09,729 And you know, the crazy thing 249 00:14:09,797 --> 00:14:13,868 about this is that this concrete 250 00:14:13,935 --> 00:14:16,204 gets stronger over time, and 251 00:14:16,271 --> 00:14:18,672 this has only been 30 days' hardening. 252 00:14:18,739 --> 00:14:22,476 This is ancient technology at work underwater 253 00:14:22,543 --> 00:14:26,113 concrete 2,000 years ahead of its time. 254 00:14:26,180 --> 00:14:30,885 It's impossible to believe that this marine mix concrete 255 00:14:30,951 --> 00:14:33,487 sat underwater and hardened. 256 00:14:33,555 --> 00:14:37,725 It's as hard as modern concrete. 257 00:14:37,792 --> 00:14:40,494 But exactly how hard is it? 258 00:14:40,561 --> 00:14:42,496 How does Roman marine concrete 259 00:14:42,564 --> 00:14:44,632 hold up to modern testing? 260 00:14:44,699 --> 00:14:47,234 For the first time, the engineering workshop has a 261 00:14:47,301 --> 00:14:50,771 sample and will test the pressure it can withstand in 262 00:14:50,838 --> 00:14:53,708 psi, pounds per square inch. 263 00:14:53,774 --> 00:14:55,509 That technology is a couple 264 00:14:55,576 --> 00:14:56,878 thousand years old, and I'd be 265 00:14:56,945 --> 00:14:59,714 surprised if it got up to 200 or 300 psi. 266 00:15:05,253 --> 00:15:08,590 Soon it becomes clear that after just 30 days' 267 00:15:08,590 --> 00:15:10,524 setting, the Roman mix concrete 268 00:15:10,591 --> 00:15:13,527 is bearing up remarkably well. 269 00:15:13,595 --> 00:15:18,732 Anything beyond 300 psi would be astonishing. 270 00:15:18,832 --> 00:15:21,535 This came in at nearly 400 psi. 271 00:15:21,635 --> 00:15:24,739 For an ancient technology, that's incredible. 272 00:15:24,806 --> 00:15:25,940 With every week, 273 00:15:26,007 --> 00:15:29,944 the concrete will get stronger and stronger. 274 00:15:30,010 --> 00:15:35,048 This concrete mix was 2,000 years ahead of its time. 275 00:15:35,115 --> 00:15:37,685 And that's without all the modern machinery used in the 276 00:15:37,752 --> 00:15:39,554 industry today. 277 00:15:39,620 --> 00:15:43,557 We're making modern concrete right behind me now. 278 00:15:43,624 --> 00:15:45,225 It's impossible to think that 279 00:15:45,292 --> 00:15:48,562 all of this modern equipment is needed to replicate what the 280 00:15:48,629 --> 00:15:55,904 ancient Romans were doing 2,000 years ago. 281 00:16:12,870 --> 00:16:14,104 Many of the biggest 282 00:16:14,172 --> 00:16:18,176 builds of the modern world are factories and places of industry. 283 00:16:18,377 --> 00:16:22,112 Even food, which used to be made in the home, is now produced on 284 00:16:22,180 --> 00:16:24,114 an industrial scale. 285 00:16:24,181 --> 00:16:28,253 In ancient times, could they have had factories like this? 286 00:16:28,320 --> 00:16:31,989 Surely impossible. 287 00:16:32,056 --> 00:16:36,126 But these strange ruins on a hillside in Southern France have 288 00:16:36,194 --> 00:16:39,097 a remarkable story to tell. 289 00:16:39,163 --> 00:16:41,131 For years, they were a puzzle. 290 00:16:41,199 --> 00:16:46,136 But now history is being rewritten. 291 00:16:46,204 --> 00:16:50,140 We normally think that it was the industrial revolution that 292 00:16:50,207 --> 00:16:52,142 gave us the modern idea of 293 00:16:52,210 --> 00:16:57,148 factories, and before that, we had cottage industries. 294 00:16:57,215 --> 00:17:03,253 However, we've now got to rewrite our understanding. 295 00:17:03,321 --> 00:17:04,755 The mysterious 296 00:17:04,822 --> 00:17:08,258 ruins are at barbegal, near the town of arles. 297 00:17:08,325 --> 00:17:11,028 And the clue to what went on 298 00:17:11,095 --> 00:17:14,165 here lies above, beyond the hillside. 299 00:17:14,231 --> 00:17:18,169 Here we find something spectacular. 300 00:17:18,235 --> 00:17:19,903 We're in Southern France at 301 00:17:19,970 --> 00:17:22,172 barbegal, and this is a Roman aqueduct. 302 00:17:22,239 --> 00:17:26,110 But it's unlike any Roman aqueduct you've seen before. 303 00:17:26,177 --> 00:17:31,181 What makes this so special is how it was put to use. 304 00:17:31,249 --> 00:17:35,987 The water from this aqueduct served a very special purpose. 305 00:17:36,053 --> 00:17:39,190 What's so significant about this site is that there were 16 306 00:17:39,256 --> 00:17:43,194 mills powered by water, right along this hillside. 307 00:17:43,261 --> 00:17:46,263 A huge series of waterwheels. 308 00:17:46,330 --> 00:17:50,000 This is something that's totally extraordinary. 309 00:17:50,068 --> 00:17:54,172 We haven't seen the like until today with modern hydro-electric 310 00:17:54,238 --> 00:17:57,875 systems. 311 00:17:57,943 --> 00:18:00,811 This is a huge undertaking. 312 00:18:00,878 --> 00:18:03,080 They actually turn a natural 313 00:18:03,148 --> 00:18:07,151 hillside into a vast watermill system. 314 00:18:07,218 --> 00:18:14,958 This is a really massive mechanical operation, and it worked. 315 00:18:15,159 --> 00:18:17,829 The Romans didn't invent the watermill. 316 00:18:17,896 --> 00:18:20,831 The ancient greeks were the first to use them. 317 00:18:20,898 --> 00:18:25,369 But nothing like barbegal had ever been built before. 318 00:18:25,436 --> 00:18:29,373 Together, these waterwheels comprised one of the biggest 319 00:18:29,440 --> 00:18:33,343 builds of the ancient world, a waterwheel super factory in 320 00:18:33,410 --> 00:18:37,848 the 2nd century A.D. Which has never been matched since. 321 00:18:37,916 --> 00:18:39,984 And that's despite waterwheels 322 00:18:40,051 --> 00:18:43,187 remaining in use for another 2,000 years. 323 00:18:43,254 --> 00:18:45,223 It wasn't until the age of steam 324 00:18:45,290 --> 00:18:49,259 that the mechanics of waterwheels were surpassed. 325 00:18:49,327 --> 00:18:53,732 But not only was barbegal massive, it was also highly 326 00:18:53,799 --> 00:18:54,999 efficient. 327 00:18:55,065 --> 00:18:58,503 It was much more advanced than any waterwheel technology that 328 00:18:58,570 --> 00:19:05,944 followed it. 329 00:19:06,011 --> 00:19:09,948 Many waterwheels, like this 17th century mill at hereford in 330 00:19:10,014 --> 00:19:13,250 england, are powered by water hitting the bottom or middle of 331 00:19:13,318 --> 00:19:16,521 the wheel. 332 00:19:16,588 --> 00:19:19,290 If we had a higher drop what we'd do is we'd be bringing the 333 00:19:19,357 --> 00:19:22,025 water in over the top and have an overshot wheel so the water 334 00:19:22,092 --> 00:19:25,263 fills all the buckets and turns it around-- more efficient, but 335 00:19:25,330 --> 00:19:27,531 you need to have that bigger drop of water. 336 00:19:27,599 --> 00:19:31,101 Without a steep incline, a stream can still 337 00:19:31,168 --> 00:19:32,436 power a waterwheel. 338 00:19:32,503 --> 00:19:36,975 But at barbegal the Romans made use of the high drop. 339 00:19:37,042 --> 00:19:40,978 The water pouring down onto the wheels -- 66 gallons per 340 00:19:41,045 --> 00:19:47,519 second-- made each of these wheels two and a half times more efficient. 341 00:19:47,586 --> 00:19:52,322 But it's not just the mills here that were an engineering marvel. 342 00:19:52,389 --> 00:19:56,528 Getting the water to them was a seemingly impossible task. 343 00:19:56,594 --> 00:20:01,032 Between the aqueduct and the mills was the top of the hill. 344 00:20:01,099 --> 00:20:02,300 What the Romans do is they 345 00:20:02,367 --> 00:20:05,803 actually physically cut a channel into the top of the 346 00:20:05,870 --> 00:20:09,407 hillside so the water can be fed through, and then it can hit 347 00:20:09,474 --> 00:20:12,342 the top of the mill with absolute force and then charge 348 00:20:12,409 --> 00:20:14,411 down 65 feet to the bottom, 349 00:20:14,478 --> 00:20:16,814 creating a huge amount of force 350 00:20:16,881 --> 00:20:18,349 and momentum. 351 00:20:18,416 --> 00:20:22,052 The massive cutting was made through solid rock. 352 00:20:22,119 --> 00:20:25,956 And it shows the incredible ambition of the Romans. 353 00:20:26,023 --> 00:20:29,894 For them, when it came to building, no obstacle was too 354 00:20:29,961 --> 00:20:31,296 big. 355 00:20:31,362 --> 00:20:33,497 What's really impossible, just think about barbegal. 356 00:20:33,564 --> 00:20:37,368 Somebody had the vision to say we'll capture water six miles 357 00:20:37,435 --> 00:20:41,039 away, build an aqueduct, stick it through a mountain, and then 358 00:20:41,106 --> 00:20:43,941 we'll build a whole set of steps of water wheels to harness all 359 00:20:44,009 --> 00:20:48,847 that energy, 16 water mills all stacked up. 360 00:20:48,914 --> 00:20:50,315 The scale was immense. 361 00:20:50,381 --> 00:20:56,387 This was able to put out about 4,5 tons of flour every day. 362 00:20:56,454 --> 00:20:59,057 But what was all this flour for? 363 00:21:03,461 --> 00:21:07,465 Today's mega-bakeries use machinery on an industrial scale 364 00:21:07,465 --> 00:21:14,071 to produce vast amounts of bread for our towns and cities. 365 00:21:14,138 --> 00:21:18,408 Why at barbegal was the huge milling complex needed? 366 00:21:18,475 --> 00:21:22,513 We know there were at least 12,500 people living in arles 367 00:21:22,580 --> 00:21:25,416 and then some more military on top of that. 368 00:21:25,483 --> 00:21:29,086 It looks like the wheels at barbegal produced enough bread 369 00:21:29,154 --> 00:21:32,357 to feed the entire population. 370 00:21:32,424 --> 00:21:35,158 Keeping people fed was all a part of the Romans' 371 00:21:35,225 --> 00:21:36,561 grand plan. 372 00:21:36,628 --> 00:21:40,564 Military might alone doesn't hold an empire together. 373 00:21:40,631 --> 00:21:44,435 Very interestingly, there is no point in having an empire if 374 00:21:44,502 --> 00:21:47,504 your people are either subversive or starving. 375 00:21:47,571 --> 00:21:49,040 So of course the way to keep 376 00:21:49,107 --> 00:21:52,442 them on side is to keep them well-fed. 377 00:21:52,510 --> 00:21:56,446 During barbegal's peak years, the vast Roman 378 00:21:56,513 --> 00:22:00,051 empire was growing at a breakneck pace, bringing people 379 00:22:00,118 --> 00:22:03,588 together into urban centers, keeping them under control, 380 00:22:03,655 --> 00:22:08,459 civilizing them, it was all part of how the empire worked. 381 00:22:08,525 --> 00:22:11,461 A city could be fed. 382 00:22:11,529 --> 00:22:17,068 The people were then free to work, to make goods. 383 00:22:17,135 --> 00:22:18,469 Goods equals wealth. 384 00:22:18,535 --> 00:22:21,339 Wealth equals power. 385 00:22:21,406 --> 00:22:22,706 A waterwheel? 386 00:22:22,773 --> 00:22:25,475 The power of the Roman empire. 387 00:22:25,542 --> 00:22:28,612 But the empire didn't go on growing forever. 388 00:22:28,679 --> 00:22:32,483 One theory as to why the Roman empire eventually declined is 389 00:22:32,550 --> 00:22:35,153 that it had so much slave labor, 390 00:22:35,219 --> 00:22:39,489 there was no incentive to embrace new technology. 391 00:22:39,557 --> 00:22:43,226 Barbegal is important because it shows the opposite. 392 00:22:43,293 --> 00:22:45,696 It's a water-powered factory. 393 00:22:45,763 --> 00:22:48,566 I think when people learn about barbegal, they're always 394 00:22:48,632 --> 00:22:50,701 shocked and amazed. 395 00:22:50,769 --> 00:22:52,203 Today we think about factories, 396 00:22:52,270 --> 00:22:54,171 we think about industrialization, we think 397 00:22:54,238 --> 00:22:55,439 about modern times. 398 00:22:55,506 --> 00:22:58,075 But here the Romans are showing us what they were able to 399 00:22:58,142 --> 00:23:00,477 achieve on a grand scale, on an 400 00:23:00,544 --> 00:23:04,448 industrialized scale, 2,000 years ago. 401 00:23:04,515 --> 00:23:06,717 I think it's rightly earned the reputation as being the 402 00:23:06,784 --> 00:23:10,321 greatest concentration of mechanical power in the ancient world. 403 00:23:10,522 --> 00:23:12,189 It's phenomenal! 404 00:23:12,256 --> 00:23:15,359 Remarkably, this hugely important archaeological 405 00:23:15,426 --> 00:23:17,528 site has only really been fully 406 00:23:17,594 --> 00:23:20,531 understood in the last few decades. 407 00:23:20,598 --> 00:23:23,533 And it's been a revelation. 408 00:23:23,533 --> 00:23:26,070 Before this, no one imagined 409 00:23:26,137 --> 00:23:28,272 such a place could exist. 410 00:23:28,339 --> 00:23:31,676 Is it possible there could be other sites like this which have 411 00:23:31,743 --> 00:23:33,677 yet to be discovered? 412 00:23:33,744 --> 00:23:36,280 The barbegal mills are a real success story. 413 00:23:36,347 --> 00:23:39,550 As a historian and archaeologist, you're constantly 414 00:23:39,617 --> 00:23:42,786 thinking maybe, just maybe there's another example like 415 00:23:42,853 --> 00:23:45,155 this that is just waiting to be found. 416 00:23:45,223 --> 00:23:48,425 And what's really interesting about them is that, in a way, 417 00:23:48,493 --> 00:23:52,562 this is the industrial revolution 16 centuries before 418 00:23:52,629 --> 00:23:59,302 the industrial revolution officially happens. 419 00:24:17,469 --> 00:24:20,773 Throughout the centuries, warfare has driven 420 00:24:20,840 --> 00:24:23,643 technology. 421 00:24:23,709 --> 00:24:25,411 Great scientific breakthroughs 422 00:24:25,478 --> 00:24:26,746 have been made in our quest for 423 00:24:26,813 --> 00:24:29,882 new means of destruction. 424 00:24:29,950 --> 00:24:32,619 Defense is a huge industry, and 425 00:24:32,686 --> 00:24:36,555 is responsible for some of our biggest builds. 426 00:24:36,623 --> 00:24:40,692 But could there have been an ancient military factory as big 427 00:24:40,759 --> 00:24:43,395 as those of today? 428 00:24:43,462 --> 00:24:47,699 This is the joint systems manufacturing center in Lima, Ohio. 429 00:24:47,901 --> 00:24:51,904 It's the home of the Abrams tank, 70 tons of imposing 430 00:24:51,971 --> 00:24:55,440 military might. 431 00:24:55,507 --> 00:24:57,442 All tanks for the U.S. army are 432 00:24:57,509 --> 00:25:01,780 built here. 433 00:25:01,847 --> 00:25:06,384 During world war ii, it mass- produced tanks at a phenomenal rate. 434 00:25:06,585 --> 00:25:09,455 Victory in Europe depended on it. 435 00:25:09,521 --> 00:25:15,194 It's still one massive factory with a highly skilled workforce. 436 00:25:15,261 --> 00:25:17,462 It's great knowing that you're building the best product 437 00:25:17,529 --> 00:25:18,931 in the world and soldiers are 438 00:25:18,998 --> 00:25:20,666 safe, one of the best-built 439 00:25:20,734 --> 00:25:26,873 tanks in the world. 440 00:25:26,940 --> 00:25:29,342 This is the first time that 441 00:25:29,409 --> 00:25:33,212 I've been on a tank, and I have to say it's a real thrill. 442 00:25:33,279 --> 00:25:34,814 I mean, up here you really get 443 00:25:34,881 --> 00:25:36,849 a most incredibly commanding 444 00:25:36,915 --> 00:25:37,482 view. 445 00:25:37,549 --> 00:25:40,687 I'm a cavalry man at heart, and it's very much like being on a 446 00:25:40,754 --> 00:25:41,888 horse. 447 00:25:41,955 --> 00:25:44,724 In many ways, the tank is the modern equivalent of 448 00:25:44,790 --> 00:25:48,627 an ancient fighting chariot, a mobile, state-of-the-art 449 00:25:48,694 --> 00:25:50,495 fighting force. 450 00:25:50,563 --> 00:25:53,566 But it's also a command center, just like chariots were, 451 00:25:53,632 --> 00:25:55,735 mobile platforms for artillery 452 00:25:55,802 --> 00:25:58,504 on the battlefield. 453 00:25:58,571 --> 00:26:01,873 It's not infrequently said, and I've often said it myself, 454 00:26:01,940 --> 00:26:04,477 that the chariot is the ancient tank. 455 00:26:04,544 --> 00:26:08,880 What it does is provide mobility. 456 00:26:08,948 --> 00:26:10,350 The fighting 457 00:26:10,417 --> 00:26:11,517 chariots of the ancient 458 00:26:11,584 --> 00:26:13,253 Egyptians were the meanest 459 00:26:13,319 --> 00:26:15,020 machines on the battlefield. 460 00:26:15,087 --> 00:26:18,757 But were they factory-made, like the tanks at Lima? 461 00:26:18,825 --> 00:26:20,759 It's almost impossible to 462 00:26:20,826 --> 00:26:26,399 believe, but over 3,000 years ago, the great pharaoh ramses ii 463 00:26:26,466 --> 00:26:28,534 had his own huge factory for the 464 00:26:28,601 --> 00:26:33,373 state-run production of these fighting machines. 465 00:26:33,440 --> 00:26:35,408 We have evidence of ramses' 466 00:26:35,475 --> 00:26:36,943 chariot factory both 467 00:26:37,009 --> 00:26:39,011 archaeologically and in tomb 468 00:26:39,078 --> 00:26:40,546 paintings, and what we can tell 469 00:26:40,613 --> 00:26:43,516 is it was on a massive scale-- 470 00:26:43,583 --> 00:26:46,552 state mass production, just like 471 00:26:46,619 --> 00:26:49,756 this tank factory. 472 00:26:49,823 --> 00:26:52,825 Ramses demanded chariots, 473 00:26:52,892 --> 00:26:55,428 masses of chariots. 474 00:26:55,495 --> 00:26:58,797 They were needed for a battle, a big battle, the battle of 475 00:26:58,864 --> 00:27:00,632 Kadesh, the greatest chariot 476 00:27:00,700 --> 00:27:04,703 battle that the world has ever seen. 477 00:27:04,770 --> 00:27:09,575 In 1274 bc, Kadesh was the culmination of the 478 00:27:09,642 --> 00:27:13,779 incredible mass production of chariots under ramses ii. 479 00:27:13,846 --> 00:27:17,450 And it was here, in the desert of modern-day Syria, that the 480 00:27:17,517 --> 00:27:20,853 Egyptian army clashed with the other superpower of the day, 481 00:27:20,920 --> 00:27:22,421 the hittites. 482 00:27:22,488 --> 00:27:26,592 With thousands of chariots on each side, this was chariot 483 00:27:26,659 --> 00:27:29,996 warfare on an unprecedented and massive scale. 484 00:27:30,063 --> 00:27:32,831 That's an awful lot of chariots on the field, and you 485 00:27:32,899 --> 00:27:35,734 imagine them swirling around in the dust. 486 00:27:35,802 --> 00:27:38,938 It's a thick dust storm, and it's a real dogfight as they're 487 00:27:39,005 --> 00:27:42,607 all trying to outmaneuver each other, and the archers to pick 488 00:27:42,674 --> 00:27:48,413 off their opponents. 489 00:27:48,480 --> 00:27:51,550 But how could so many chariots have been made? 490 00:27:51,617 --> 00:27:52,584 And where? 491 00:27:52,651 --> 00:27:54,019 The factory that produced the 492 00:27:54,086 --> 00:27:56,088 Egyptian chariots must have been 493 00:27:56,155 --> 00:27:58,990 massive, big enough to supply 494 00:27:59,057 --> 00:28:02,094 the huge numbers of chariots needed for the war with the 495 00:28:02,161 --> 00:28:05,498 hittites. 496 00:28:05,565 --> 00:28:06,833 And a possible site has been 497 00:28:06,900 --> 00:28:11,371 identified at pi-ramesse in the nile delta. 498 00:28:11,438 --> 00:28:14,140 What we have is stables for 499 00:28:14,207 --> 00:28:16,776 something like 480 horses, which 500 00:28:16,843 --> 00:28:19,478 means 240 chariots. 501 00:28:19,546 --> 00:28:21,013 We have a training ground, and 502 00:28:21,080 --> 00:28:24,484 we have a place which is said by 503 00:28:24,551 --> 00:28:27,586 some people to be a chariot factory. 504 00:28:27,653 --> 00:28:30,989 The site on the nile has yet to be fully excavated. 505 00:28:31,190 --> 00:28:33,659 But one thing we know for sure 506 00:28:33,726 --> 00:28:35,795 is that, remarkably, the factory 507 00:28:35,862 --> 00:28:38,663 used an assembly line, just like 508 00:28:38,730 --> 00:28:40,532 the tank factory at Lima. 509 00:28:40,600 --> 00:28:42,001 So here we are at the 510 00:28:42,067 --> 00:28:44,069 assembly line, and you can see 511 00:28:44,136 --> 00:28:45,804 tank after tank after tank 512 00:28:45,872 --> 00:28:47,073 stretching back there. 513 00:28:47,140 --> 00:28:49,809 You're taking pre-formed pieces, 514 00:28:49,875 --> 00:28:51,411 and you're bringing them to an 515 00:28:51,478 --> 00:28:52,945 assembly plant, and skilled 516 00:28:53,011 --> 00:28:56,182 workers are putting things together. 517 00:28:56,248 --> 00:28:57,549 It is almost impossible to 518 00:28:57,616 --> 00:28:59,050 imagine that over 3,000 years 519 00:28:59,117 --> 00:29:01,887 ago the manufacturing processes, 520 00:29:01,955 --> 00:29:04,023 the systems for making military 521 00:29:04,090 --> 00:29:05,757 hardware would be the same as 522 00:29:05,825 --> 00:29:07,692 they are in the 21st century, 523 00:29:07,759 --> 00:29:08,960 but they were. 524 00:29:09,027 --> 00:29:10,796 It was the same principle-- 525 00:29:10,863 --> 00:29:14,700 assembly line factory work. 526 00:29:14,767 --> 00:29:16,536 Henry Ford is known as the 527 00:29:16,603 --> 00:29:18,704 creator of the production line 528 00:29:18,770 --> 00:29:21,673 in the 20th century, but 3,000 529 00:29:21,740 --> 00:29:23,709 years ago, impossible to 530 00:29:23,776 --> 00:29:25,710 believe, the Egyptians did the 531 00:29:25,777 --> 00:29:28,213 same-- an assembly line that 532 00:29:28,280 --> 00:29:29,848 churns out relentlessly chariot 533 00:29:29,915 --> 00:29:31,817 after chariot after chariot. 534 00:29:31,884 --> 00:29:33,552 On the floor of the 535 00:29:33,620 --> 00:29:35,588 tank factory, the individual 536 00:29:35,654 --> 00:29:37,589 components come together. 537 00:29:37,657 --> 00:29:40,725 They're state-of-the-art and made by specialist teams. 538 00:29:40,793 --> 00:29:43,728 It was just the same in the chariot factory. 539 00:29:43,796 --> 00:29:47,967 First, the body of the chariot-- lightweight wood 540 00:29:48,034 --> 00:29:49,735 curved into shape by steaming 541 00:29:49,802 --> 00:29:54,140 it, just big enough for two standing men. 542 00:29:54,207 --> 00:29:56,142 The undercarriage was a fixed 543 00:29:56,209 --> 00:29:58,009 axle and a central pole made by 544 00:29:58,076 --> 00:30:00,746 one artificially bent piece of wood. 545 00:30:00,813 --> 00:30:02,148 Quite a large wheelbase directly 546 00:30:02,215 --> 00:30:05,017 beneath the body to keep the chariot stable. 547 00:30:05,084 --> 00:30:06,751 The frame for the horses is also 548 00:30:06,818 --> 00:30:08,620 made of bent wood, and it 549 00:30:08,688 --> 00:30:11,157 attaches to the end of the pole. 550 00:30:11,223 --> 00:30:15,026 You can't have a chariot without wheels. 551 00:30:15,094 --> 00:30:16,761 One quick assembly. 552 00:30:16,828 --> 00:30:21,501 A deadly, mobile fighting machine. 553 00:30:21,567 --> 00:30:24,036 The Egyptians understood the importance of 554 00:30:24,103 --> 00:30:26,171 using the perfect materials, and 555 00:30:26,238 --> 00:30:28,574 imported wood especially, in 556 00:30:28,641 --> 00:30:31,978 particular, ash. 557 00:30:32,045 --> 00:30:34,046 Even today, one specialty 558 00:30:34,113 --> 00:30:35,581 builder of sports cars in 559 00:30:35,648 --> 00:30:38,150 england still uses ash just as 560 00:30:38,217 --> 00:30:41,521 the ancient Egyptians did. 561 00:30:41,587 --> 00:30:43,722 This is the Morgan car factory, 562 00:30:43,789 --> 00:30:45,257 where skilled craftsmen have 563 00:30:45,325 --> 00:30:47,026 been assembling cars in this way 564 00:30:47,093 --> 00:30:51,663 for over 100 years. 565 00:30:51,730 --> 00:30:54,733 Ash of course would be ideal for a combat vehicle, a chariot, 566 00:30:54,801 --> 00:30:57,769 for the same reasons that we use it-- it's not only extremely 567 00:30:57,836 --> 00:30:59,604 strong, it's lightweight. 568 00:30:59,671 --> 00:31:00,940 The lighter you could make a 569 00:31:01,007 --> 00:31:02,807 structure like that, the easier 570 00:31:02,874 --> 00:31:05,810 the horses could pull it, the more flexible it would be and a 571 00:31:05,878 --> 00:31:09,815 more effective fighting machine. 572 00:31:09,882 --> 00:31:11,784 Being flexible, it can act as a 573 00:31:11,851 --> 00:31:12,785 shock absorber. 574 00:31:12,852 --> 00:31:14,819 It's the same with us here in Morgan. 575 00:31:14,886 --> 00:31:16,688 The frame will flex and bend 576 00:31:16,756 --> 00:31:18,291 with the chassis, and this all 577 00:31:18,357 --> 00:31:20,158 adds to the road-holding and 578 00:31:20,226 --> 00:31:21,928 the handling of the cars. 579 00:31:21,995 --> 00:31:25,030 The factory here makes around 100 cars a month, 580 00:31:25,097 --> 00:31:29,669 handcrafted with skill and precision. 581 00:31:29,736 --> 00:31:33,839 Ramses ii needed chariots in their thousands. 582 00:31:33,905 --> 00:31:35,941 The fact that his chariots could 583 00:31:36,008 --> 00:31:38,209 be mass-produced was in itself a 584 00:31:38,276 --> 00:31:41,914 source of wonder and terror for his enemies. 585 00:31:41,980 --> 00:31:45,317 Ramses' systems were so 586 00:31:45,384 --> 00:31:47,786 advanced, so efficient in 587 00:31:47,853 --> 00:31:51,056 producing the great numbers of 588 00:31:51,123 --> 00:31:53,859 military vehicles that he needed. 589 00:31:53,926 --> 00:31:58,264 It's almost impossible to conceive that factories of this 590 00:31:58,331 --> 00:32:01,367 scale existed 3,000 years ago, 591 00:32:01,433 --> 00:32:07,305 but they did. 592 00:32:25,773 --> 00:32:28,408 Some of the most iconic buildings ever 593 00:32:28,475 --> 00:32:30,643 constructed are huge cathedrals 594 00:32:30,711 --> 00:32:36,516 such as notre dame in Paris and st Paul's in London. 595 00:32:36,583 --> 00:32:38,318 But incredibly, one of the 596 00:32:38,386 --> 00:32:40,021 biggest builds in history is a 597 00:32:40,088 --> 00:32:44,392 cathedral from ancient times. 598 00:32:44,458 --> 00:32:46,693 In 6th-century constantinople, 599 00:32:46,761 --> 00:32:48,596 when the magnificent cathedral 600 00:32:48,663 --> 00:32:51,798 of hagia Sophia rose from the ground, it was as if the 601 00:32:51,866 --> 00:32:55,603 impossible had happened. 602 00:32:55,669 --> 00:32:57,071 This is the hagia Sophia. 603 00:32:57,138 --> 00:32:58,606 It is one of the most impressive 604 00:32:58,673 --> 00:33:01,175 architectural constructions in the world. 605 00:33:01,242 --> 00:33:02,542 It exerted an influence for 606 00:33:02,609 --> 00:33:05,612 1,000 years after its construction. 607 00:33:05,679 --> 00:33:08,481 "Hagia Sophia" means "holy or 608 00:33:08,549 --> 00:33:10,718 divine wisdom" in turkish, and 609 00:33:10,784 --> 00:33:12,753 the building is the supreme 610 00:33:12,820 --> 00:33:14,588 masterpiece of byzantine 611 00:33:14,655 --> 00:33:16,624 architecture, and for almost 612 00:33:16,690 --> 00:33:18,625 1,000 years, it was the biggest 613 00:33:18,693 --> 00:33:21,162 cathedral in the whole world. 614 00:33:21,228 --> 00:33:25,366 Still standing after 1,500 years, with minarets 615 00:33:25,433 --> 00:33:29,637 added at a later date, this was an incredible build, with 616 00:33:29,704 --> 00:33:33,640 techniques centuries ahead of its time, a Roman Christian 617 00:33:33,707 --> 00:33:39,446 cathedral that was a revolution in architecture. 618 00:33:39,513 --> 00:33:41,648 This is such an amazing space. 619 00:33:41,715 --> 00:33:43,650 You've got something that's intact, something that's 620 00:33:43,717 --> 00:33:45,585 constructed in the 6th century 621 00:33:45,653 --> 00:33:47,788 A.D., and the thing is, it's 622 00:33:47,855 --> 00:33:49,190 just hard to get a sense of how 623 00:33:49,256 --> 00:33:50,523 massive this space is because 624 00:33:50,590 --> 00:33:54,227 there's so many openings, there's so much light. 625 00:33:54,294 --> 00:33:55,795 It's almost impossible to 626 00:33:55,862 --> 00:33:58,264 imagine what people thought of 627 00:33:58,331 --> 00:34:00,133 it when they first saw it. 628 00:34:00,201 --> 00:34:01,635 They must have thought that they 629 00:34:01,702 --> 00:34:03,670 were looking at something impossible. 630 00:34:03,737 --> 00:34:05,371 They wouldn't have understood 631 00:34:05,438 --> 00:34:07,507 how it stayed upright. 632 00:34:07,574 --> 00:34:09,676 A lot of people thought that god 633 00:34:09,744 --> 00:34:12,413 himself was holding the building. 634 00:34:12,480 --> 00:34:13,881 That's how special it was. 635 00:34:13,947 --> 00:34:17,150 And this was exactly the intention. 636 00:34:17,217 --> 00:34:19,385 The man behind it, the emperor 637 00:34:19,453 --> 00:34:22,822 Justinian, needed to assert his political power. 638 00:34:22,889 --> 00:34:24,757 To do this, he wanted to be 639 00:34:24,824 --> 00:34:29,163 linked with god in the most visible way. 640 00:34:29,230 --> 00:34:30,764 He wanted it to represent not 641 00:34:30,830 --> 00:34:32,699 only his greatness on earth, but 642 00:34:32,766 --> 00:34:34,701 god's greatness in heaven, and 643 00:34:34,769 --> 00:34:36,570 to draw that link for people to 644 00:34:36,637 --> 00:34:40,708 say, "I am god's representative on earth." 645 00:34:40,774 --> 00:34:44,311 In the 6th century, the Roman empire was based in 646 00:34:44,378 --> 00:34:47,181 constantinople, modern-day Istanbul. 647 00:34:47,247 --> 00:34:49,315 But the empire was fading. 648 00:34:49,382 --> 00:34:50,917 Justinian knew that if he didn't 649 00:34:50,984 --> 00:34:53,320 make his mark in some grand way, 650 00:34:53,387 --> 00:34:56,456 he would be just a footnote in history. 651 00:34:56,523 --> 00:34:58,591 He wanted to be great. 652 00:34:58,658 --> 00:34:59,859 He was determined that as well 653 00:34:59,926 --> 00:35:02,196 as being something massive, his 654 00:35:02,263 --> 00:35:03,397 cathedral was going to be 655 00:35:03,464 --> 00:35:05,599 something completely new. 656 00:35:05,666 --> 00:35:07,734 So he didn't go to the master builders of his age. 657 00:35:07,801 --> 00:35:09,703 He went to mathematicians. 658 00:35:09,770 --> 00:35:12,205 He depends upon these experts of 659 00:35:12,273 --> 00:35:13,840 math and geometry and science to 660 00:35:13,907 --> 00:35:16,476 go in a new direction, to create 661 00:35:16,543 --> 00:35:18,612 something that no one had ever seen before. 662 00:35:18,679 --> 00:35:20,581 To understand it, we need to 663 00:35:20,647 --> 00:35:22,348 start with the dome. 664 00:35:22,415 --> 00:35:26,453 The dome is the most impossible achievement. 665 00:35:26,520 --> 00:35:30,757 It's 102 feet across and 180 feet high. 666 00:35:30,824 --> 00:35:32,759 It's huge. 667 00:35:32,826 --> 00:35:34,494 It's broader than the dome of 668 00:35:34,561 --> 00:35:36,330 the capitol building, and that 669 00:35:36,397 --> 00:35:40,234 was built 1,300 years later. 670 00:35:40,301 --> 00:35:42,369 But the most amazing thing is 671 00:35:42,435 --> 00:35:43,770 that the dome doesn't seem to be 672 00:35:43,837 --> 00:35:48,775 resting on anything solid. 673 00:35:48,842 --> 00:35:51,712 Essentially you have this massive dome, which seems to 674 00:35:51,779 --> 00:35:55,782 just rest lightly on these 40 windows so it's something that's 675 00:35:55,850 --> 00:35:58,786 ethereal, almost light about it. 676 00:35:58,853 --> 00:36:02,456 And for a dome to be built on a square base rather 677 00:36:02,522 --> 00:36:05,658 than a round one was something completely new. 678 00:36:05,726 --> 00:36:09,929 For the Romans to achieve this was truly remarkable. 679 00:36:09,996 --> 00:36:11,799 These four piers are 680 00:36:11,866 --> 00:36:13,867 essentially building supports, 681 00:36:13,933 --> 00:36:16,804 and in the hagia Sophia, they're huge. 682 00:36:16,871 --> 00:36:20,406 They were built to support the dome. 683 00:36:20,473 --> 00:36:23,811 Well, four arches were built on top of the columns. 684 00:36:23,877 --> 00:36:25,812 Then, the spaces in between were 685 00:36:25,880 --> 00:36:27,681 filled with masonry. 686 00:36:27,748 --> 00:36:30,417 They fill in the upper corners of the space and so form a 687 00:36:30,484 --> 00:36:34,520 circular support for the dome. 688 00:36:34,587 --> 00:36:37,290 This was a giant leap in architecture. 689 00:36:37,357 --> 00:36:39,826 It must have been incredible then, because today it still 690 00:36:39,893 --> 00:36:45,265 looks awe-inspiring. 691 00:36:45,333 --> 00:36:49,837 Hagia Sophia is huge, about 65,000 square feet, 692 00:36:49,904 --> 00:36:54,808 but the speed of its building was impossible, too. 693 00:36:54,875 --> 00:36:57,645 Normally, cathedrals took decades to build. 694 00:36:57,712 --> 00:36:59,280 The construction of notre dame 695 00:36:59,346 --> 00:37:02,850 hundreds of years later took over a century. 696 00:37:02,917 --> 00:37:07,688 And just the dome of the capitol building took 11 years. 697 00:37:07,755 --> 00:37:09,657 This is a large structure 698 00:37:09,723 --> 00:37:11,925 that's built in a mere five years. 699 00:37:11,991 --> 00:37:16,830 That is incredible. 700 00:37:16,897 --> 00:37:18,732 To give a modern comparison, 701 00:37:18,799 --> 00:37:20,868 the Burj Khalifa in Dubai, which 702 00:37:20,935 --> 00:37:22,335 is the tallest building in the 703 00:37:22,402 --> 00:37:24,605 whole world, took six years, and 704 00:37:24,672 --> 00:37:25,873 that's with all the modern 705 00:37:25,940 --> 00:37:27,741 technology that we now have. 706 00:37:27,808 --> 00:37:29,877 That is a tribute to Justinian's 707 00:37:29,944 --> 00:37:33,714 vision to make this engineering miracle happen. 708 00:37:56,820 --> 00:37:59,689 Some of the biggest builds of the ancient world were 709 00:37:59,689 --> 00:38:02,159 factories and places of industry. 710 00:38:02,226 --> 00:38:05,896 And, just like today, some of the most impressive of these 711 00:38:05,963 --> 00:38:07,430 were built because of our 712 00:38:07,497 --> 00:38:11,534 insatiable desire for precious metal. 713 00:38:11,602 --> 00:38:13,270 The Romans' need for copper and 714 00:38:13,336 --> 00:38:19,308 silver brought them here, to rio tinto in Spain. 715 00:38:19,376 --> 00:38:21,178 And for 2,000 years, the mine 716 00:38:21,244 --> 00:38:28,185 held a dark secret deep beneath the surface. 717 00:38:28,251 --> 00:38:30,853 This is the Rio Tinto mine in 718 00:38:30,921 --> 00:38:33,457 the heart of andalucia in Southern Spain. 719 00:38:33,523 --> 00:38:37,327 It's absolutely vast, almost 20 square miles. 720 00:38:37,394 --> 00:38:40,664 The first people to start exploiting metals in these hills 721 00:38:40,731 --> 00:38:43,267 were over 5,000 years ago. 722 00:38:43,334 --> 00:38:47,871 In Roman hands, this mine became the single greatest mining 723 00:38:47,938 --> 00:38:53,744 complex in the whole of the ancient world. 724 00:38:53,811 --> 00:38:57,347 And it was here, in 1919, that an astonishing 725 00:38:57,414 --> 00:39:00,484 discovery was made 726 00:39:00,550 --> 00:39:04,755 a huge wooden wheel buried deep in the ground. 727 00:39:04,822 --> 00:39:06,490 Further investigation revealed 728 00:39:06,557 --> 00:39:10,360 that it was almost 2,000 years old. 729 00:39:10,427 --> 00:39:12,195 But what was it for? 730 00:39:12,262 --> 00:39:18,202 The answer is almost impossible to believe. 731 00:39:18,269 --> 00:39:21,238 A clue was found here, at a gold 732 00:39:21,305 --> 00:39:25,641 mine in Dolaucothi in Southern wales-- 733 00:39:25,709 --> 00:39:29,513 a similar wheel and well- preserved enough for a 734 00:39:29,579 --> 00:39:31,715 scaled-down replica to be made. 735 00:39:31,782 --> 00:39:35,585 Remains of that wheel were found 150 foot down, so far 736 00:39:35,653 --> 00:39:36,919 down that it's reasonable to 737 00:39:36,986 --> 00:39:39,523 expect that more than one wheel were used. 738 00:39:39,590 --> 00:39:40,856 And this is a replica of what 739 00:39:40,923 --> 00:39:43,527 one of those wheels may have looked like. 740 00:39:43,593 --> 00:39:46,263 It became clear that the wheel was used to lift 741 00:39:46,329 --> 00:39:50,400 water to prevent the mine from flooding. 742 00:39:50,467 --> 00:39:53,537 Water from the bottom was scooped up and then fell out at 743 00:39:53,604 --> 00:39:57,241 the top into a channel that drained it away. 744 00:39:57,307 --> 00:39:59,610 And someone must have stood deep 745 00:39:59,677 --> 00:40:02,546 underground turning the wheel. 746 00:40:02,613 --> 00:40:04,548 What a horrendous job. 747 00:40:04,615 --> 00:40:10,553 A human hamster in near pitch- black conditions. 748 00:40:10,621 --> 00:40:14,390 The Romans were masters of waterwheel technology, but with 749 00:40:14,457 --> 00:40:18,561 a waterwheel, normally moving water turns the wheel. 750 00:40:18,628 --> 00:40:22,299 At both Dolaucothi and at Rio Tinto, what the Romans did was 751 00:40:22,365 --> 00:40:24,568 turn that concept on its head. 752 00:40:24,635 --> 00:40:25,836 They used manpower to turn the 753 00:40:25,903 --> 00:40:29,305 wheels, and then the wheels moved the water. 754 00:40:29,372 --> 00:40:32,575 Move the water, drain the mine, miners work. 755 00:40:32,642 --> 00:40:35,579 Genius. 756 00:40:35,646 --> 00:40:37,980 But could a large wooden wheel really have been 757 00:40:38,048 --> 00:40:40,517 any use here at Rio Tinto? 758 00:40:40,584 --> 00:40:42,452 This mine is massive, and the 759 00:40:42,519 --> 00:40:46,990 Roman shafts went deep into the earth. 760 00:40:47,057 --> 00:40:49,593 We now know that at Rio Tinto, 761 00:40:49,660 --> 00:40:50,794 the use of these wheels was 762 00:40:50,860 --> 00:40:54,997 taken to impossible extremes-- 763 00:40:55,064 --> 00:40:57,601 underground caverns, carved by 764 00:40:57,668 --> 00:41:00,604 hand from the earth, and inside? 765 00:41:00,671 --> 00:41:02,739 Eight pairs of huge waterwheels 766 00:41:02,805 --> 00:41:06,477 powered by slaves, walking the wheels. 767 00:41:11,548 --> 00:41:14,485 To a modern engineer it would seem incredible. 768 00:41:14,485 --> 00:41:16,553 To the ancients, it must have 769 00:41:16,619 --> 00:41:17,720 seemed impossible. 770 00:41:17,787 --> 00:41:19,456 But it was an impossible task 771 00:41:19,523 --> 00:41:21,858 that the Romans faced and mastered. 772 00:41:21,925 --> 00:41:23,627 This was ancient engineering 773 00:41:23,693 --> 00:41:26,028 on a massive scale, and it made 774 00:41:26,095 --> 00:41:28,631 the impossible possible. 775 00:41:28,698 --> 00:41:30,967 The wheels were probably prefabricated and 776 00:41:31,034 --> 00:41:33,736 constructed within the mine. 777 00:41:33,803 --> 00:41:35,604 Building a whole series of these 778 00:41:35,671 --> 00:41:39,642 huge waterwheels underground is almost beyond belief. 779 00:41:39,709 --> 00:41:41,644 Today it would be incredible. 780 00:41:41,711 --> 00:41:44,881 2,000 years ago, simply impossible. 781 00:41:44,947 --> 00:41:47,583 As the slaves trod the wheels, 782 00:41:47,651 --> 00:41:48,852 the water was channeled from 783 00:41:48,918 --> 00:41:50,786 one pair to the other, 784 00:41:50,854 --> 00:41:54,724 eventually rising over 100 feet before being drawn to the 785 00:41:54,791 --> 00:41:58,662 surface by a huge Archimedes screw. 786 00:41:58,729 --> 00:42:00,897 This wasn't hell on earth. 787 00:42:00,963 --> 00:42:02,465 It was hell deep within the 788 00:42:02,532 --> 00:42:05,134 earth, dark, hot and working 789 00:42:05,202 --> 00:42:07,903 with toxic, mineral-soaked water. 790 00:42:07,970 --> 00:42:09,872 The slaves who operated these 791 00:42:09,939 --> 00:42:13,008 waterwheels had the worst job in the whole mine. 792 00:42:13,075 --> 00:42:14,644 Their life expectancy once they 793 00:42:14,711 --> 00:42:17,680 got down here was about 12 to 16 months. 794 00:42:17,747 --> 00:42:19,014 It was that poisonous, and they 795 00:42:19,081 --> 00:42:21,684 were constantly coated in the water. 796 00:42:21,751 --> 00:42:24,387 And when they finally died, which they inevitably did, the 797 00:42:24,454 --> 00:42:28,758 Romans didn't even bother taking their bodies to the surface. 798 00:42:28,825 --> 00:42:31,827 But whatever the terror of the wheels, they were 799 00:42:31,894 --> 00:42:33,764 truly an ancient wonder, an 800 00:42:33,831 --> 00:42:36,432 incredible, fantastic construction. 801 00:42:39,135 --> 00:42:42,738 Unbelievable structures built with techniques thousands of 802 00:42:42,738 --> 00:42:46,709 years ahead of their time, the biggest builds of the ancient 803 00:42:46,776 --> 00:42:50,447 world were as astonishing and awe-inspiring as anything built 804 00:42:50,514 --> 00:42:53,082 today, a world of wonder, of 805 00:42:53,150 --> 00:42:57,486 terror, and of the impossible made real.