1 00:00:01,201 --> 00:00:02,935 NARRATOR: They're watching you. 2 00:00:03,002 --> 00:00:07,539 More than 5,000 satellites circle the Earth. 3 00:00:07,607 --> 00:00:11,577 Every day, they uncover new, mysterious phenomena 4 00:00:11,611 --> 00:00:13,645 that defy explanation. 5 00:00:15,482 --> 00:00:18,484 Terror stalks an Arizona ghost town. 6 00:00:18,551 --> 00:00:19,785 There were those who believed he had 7 00:00:19,886 --> 00:00:22,855 supernatural powers and couldn't be shot. 8 00:00:22,889 --> 00:00:25,958 NARRATOR: The wrath of Genghis Khan. 9 00:00:26,025 --> 00:00:30,195 Even to this day, it's known as the City of Screams. 10 00:00:30,230 --> 00:00:33,365 NARRATOR: And the miracle waters of the New World. 11 00:00:33,433 --> 00:00:36,602 This water gave them protection against 12 00:00:36,636 --> 00:00:39,038 terrifying diseases. 13 00:00:39,105 --> 00:00:43,142 Baffling phenomena, mysteries from space. 14 00:00:43,176 --> 00:00:45,044 What on Earth are they? 15 00:00:45,078 --> 00:00:47,146 [theme music playing] 16 00:01:04,998 --> 00:01:09,101 NARRATOR: March 11th, 2021. 17 00:01:09,135 --> 00:01:12,538 High over the Arizona mountains, 18 00:01:12,605 --> 00:01:15,107 a satellite captures a strange structure 19 00:01:15,141 --> 00:01:17,042 amongst the barren peaks. 20 00:01:17,077 --> 00:01:20,245 This is a really intriguing image, because this 21 00:01:20,280 --> 00:01:23,882 is surrounded by thousands of square miles of desert. 22 00:01:23,950 --> 00:01:26,485 NARRATOR: Image analysis suggests the structure 23 00:01:26,552 --> 00:01:31,690 consists of vast pieces of stone spread across 1,000 acres, 24 00:01:31,758 --> 00:01:35,494 some at elevations above 5,000 feet. 25 00:01:35,561 --> 00:01:37,529 BELLINGER: Some don't even have complete walls, 26 00:01:37,564 --> 00:01:41,133 so whatever is here, it's in ruins. 27 00:01:47,540 --> 00:01:50,576 What's really striking about this image is, geologically, 28 00:01:50,610 --> 00:01:52,111 we're really high up. 29 00:01:53,546 --> 00:01:57,216 NARRATOR: Drawn by the unexplained alpine structure, 30 00:01:57,250 --> 00:02:00,552 geologist Martin Pepper is traveling into the mountains 31 00:02:00,587 --> 00:02:01,653 to investigate. 32 00:02:03,289 --> 00:02:06,325 Why would people haul all this material way up here 33 00:02:06,392 --> 00:02:08,961 into the hills? It doesn't make sense. 34 00:02:12,565 --> 00:02:14,266 NARRATOR: Beneath these mountains are seams 35 00:02:14,333 --> 00:02:17,603 of gold, silver, and copper. 36 00:02:17,670 --> 00:02:21,206 Arizona is dotted with crumbling mining towns, 37 00:02:21,274 --> 00:02:24,243 but Pepper doesn't buy this explanation. 38 00:02:24,277 --> 00:02:27,112 Typically, these settlements literally 39 00:02:27,147 --> 00:02:28,780 exist right where they're mining, 40 00:02:28,848 --> 00:02:31,216 and so we would see big tailings coming out of some of 41 00:02:31,284 --> 00:02:34,086 these slopes, but I'm not seeing that here. 42 00:02:36,055 --> 00:02:38,490 NARRATOR: From space, it's impossible to assess 43 00:02:38,558 --> 00:02:40,659 the age of these structures, 44 00:02:40,693 --> 00:02:44,263 but clues can lie in the dirt. 45 00:02:44,297 --> 00:02:45,330 Ah, look at this. 46 00:02:49,369 --> 00:02:51,270 This is not recent. 47 00:02:51,304 --> 00:02:53,172 That's old lead solder, 48 00:02:53,239 --> 00:02:56,108 and so we're talking about the 19th century. 49 00:02:59,412 --> 00:03:02,381 NARRATOR: Ascending to the site in the satellite image, 50 00:03:02,448 --> 00:03:06,351 Pepper is prepared for 19th-century ruins. 51 00:03:06,386 --> 00:03:07,986 Check that out. 52 00:03:11,024 --> 00:03:13,358 NARRATOR: He's not prepared for this. 53 00:03:17,330 --> 00:03:19,965 Jeez! Look at the scale of this. 54 00:03:23,536 --> 00:03:25,971 This is monumental. 55 00:03:28,374 --> 00:03:32,544 NARRATOR: The satellite has captured significant structures. 56 00:03:32,612 --> 00:03:36,014 There's evidence of almost 40 buildings, heavily 57 00:03:36,082 --> 00:03:40,319 fortified, with thousands of tons of stacked stone. 58 00:03:40,353 --> 00:03:43,188 Just the width of these walls, you know, 59 00:03:43,223 --> 00:03:45,524 2, 3 feet thick, 60 00:03:45,558 --> 00:03:49,361 shows that whoever built this wanted it fortified 61 00:03:49,395 --> 00:03:51,563 and really strong. 62 00:03:51,631 --> 00:03:55,300 Why would something this big be 63 00:03:55,368 --> 00:03:57,135 out here in the middle of nowhere? 64 00:03:59,105 --> 00:04:01,540 NARRATOR: The geologist returns to the image 65 00:04:01,574 --> 00:04:04,209 that lured him here. 66 00:04:04,244 --> 00:04:06,912 Looking at this image, 67 00:04:06,979 --> 00:04:09,381 zooming in over here, 68 00:04:09,448 --> 00:04:12,551 I can see this green area. 69 00:04:12,585 --> 00:04:15,420 NARRATOR: Pepper heads west. 70 00:04:20,827 --> 00:04:22,761 There it is. Look at that. 71 00:04:26,232 --> 00:04:28,333 Ah, and there's the spring right up there. 72 00:04:31,404 --> 00:04:34,239 NARRATOR: The spring and 19th-century ruins 73 00:04:34,274 --> 00:04:35,540 sit in perhaps 74 00:04:35,608 --> 00:04:38,510 the only navigable route between the Dos Cabezas 75 00:04:38,544 --> 00:04:40,979 and Chiricahua Mountains. 76 00:04:41,014 --> 00:04:45,284 PEPPER: These mountains block what we have west to California, 77 00:04:45,351 --> 00:04:48,520 so this must be some sort of mountain pass. 78 00:04:50,590 --> 00:04:53,925 NARRATOR: Via this mountain pass, it's 400 miles 79 00:04:53,960 --> 00:04:56,261 to the Golden State of California, 80 00:04:56,296 --> 00:04:58,363 the last leg in the most 81 00:04:58,431 --> 00:05:01,933 treacherous migrant route in U.S. history. 82 00:05:01,968 --> 00:05:04,936 In the mid to late 19th century, California was 83 00:05:04,971 --> 00:05:07,539 the destination for fortune seekers, 84 00:05:07,573 --> 00:05:11,276 but getting to California was a very dangerous proposition. 85 00:05:11,310 --> 00:05:14,313 [banjo music playing] 86 00:05:14,380 --> 00:05:16,081 NARRATOR: Census records show that between 87 00:05:16,115 --> 00:05:19,484 1848 and the mid-1850s, 88 00:05:19,518 --> 00:05:23,555 more than 300,000 people flood into California, 89 00:05:23,589 --> 00:05:26,058 lured by the promise of gold. 90 00:05:30,096 --> 00:05:34,533 Wagon trains snake through Arizona's mountain passes. 91 00:05:34,600 --> 00:05:38,337 This water would have been extremely valuable in one 92 00:05:38,404 --> 00:05:41,973 of their stops off as they headed towards the west. 93 00:05:44,811 --> 00:05:49,181 NARRATOR: Disease, starvation, and fatal accidents are common. 94 00:05:49,215 --> 00:05:53,018 Tens of thousands failed to finish a journey which averages 95 00:05:53,085 --> 00:05:55,220 10 graves per mile. 96 00:05:55,287 --> 00:05:57,456 Settlers had to literally run 97 00:05:57,490 --> 00:06:00,459 the gauntlet to go through these passes. 98 00:06:00,493 --> 00:06:02,728 JANULIS: The Spanish name for this pass is 99 00:06:02,795 --> 00:06:05,464 Puerto del Dado, Pass of the Die, 100 00:06:05,498 --> 00:06:07,466 and that's not die as in death, 101 00:06:07,500 --> 00:06:09,901 but as in gambling dice. 102 00:06:09,969 --> 00:06:12,270 Coming through here means you're gambling with your life. 103 00:06:16,209 --> 00:06:18,910 NARRATOR: One gambler not prepared to lose 104 00:06:18,978 --> 00:06:22,547 is New York businessman John Butterfield. 105 00:06:22,582 --> 00:06:25,884 Butterfield's stagecoach was the first truly 106 00:06:25,918 --> 00:06:28,487 transcontinental postal service 107 00:06:28,521 --> 00:06:30,922 and it ran all the way from St. Louis, Missouri, 108 00:06:30,990 --> 00:06:32,457 to San Francisco. 109 00:06:33,926 --> 00:06:36,661 NARRATOR: The massive migration west triggers 110 00:06:36,729 --> 00:06:40,298 a fresh challenge -- How to haul the U.S. mail 111 00:06:40,333 --> 00:06:42,567 to California. 112 00:06:42,602 --> 00:06:45,170 In 1857, Butterfield wins 113 00:06:45,204 --> 00:06:48,874 America's largest ever land mail contract -- 114 00:06:48,908 --> 00:06:53,378 2,800 miles, five times the length of the U.K., 115 00:06:53,446 --> 00:06:56,581 through some of the most treacherous terrain on Earth 116 00:06:56,649 --> 00:06:58,049 in a stagecoach. 117 00:06:58,985 --> 00:07:01,052 John Butterfield had a statement 118 00:07:01,120 --> 00:07:03,121 that really stood out -- "Remember boys, 119 00:07:03,189 --> 00:07:05,724 "nothing on God's Green Earth should stop the mail from 120 00:07:05,792 --> 00:07:07,459 getting through." 121 00:07:08,294 --> 00:07:10,729 NARRATOR: Butterfield rounds up 200 coaches, 122 00:07:10,797 --> 00:07:16,435 almost 2,000 horses and mules, and hires 1,200 men. 123 00:07:16,469 --> 00:07:18,336 To win the contract, 124 00:07:18,404 --> 00:07:22,474 He's promised to complete the route in 25 days, 125 00:07:22,541 --> 00:07:28,146 leaving him no choice but to navigate the Pass of the Die. 126 00:07:28,214 --> 00:07:30,749 A small staging post was established at the head of 127 00:07:30,816 --> 00:07:32,117 the pass where 128 00:07:32,151 --> 00:07:35,754 a postal rider would stop for a rest before pressing all 129 00:07:35,822 --> 00:07:37,255 the way on to California. 130 00:07:38,524 --> 00:07:41,460 But a thousand-acre fortified structure is 131 00:07:41,494 --> 00:07:44,663 far more than a small trading post. 132 00:07:45,998 --> 00:07:48,867 PEPPER: Why would this fort be so important 133 00:07:48,901 --> 00:07:51,403 right here? There must have been something 134 00:07:51,437 --> 00:07:55,340 else leaving everybody terrified of a possible attack. 135 00:08:00,179 --> 00:08:04,049 NARRATOR: Coming up, mass slaughter in the mountains. 136 00:08:04,116 --> 00:08:08,220 This place has a long history of bloodshed and unrest. 137 00:08:08,254 --> 00:08:12,224 NARRATOR: And the lost swamp people of South Carolina. 138 00:08:12,258 --> 00:08:15,360 JANULIS: It was the first attempt to settle the shores 139 00:08:15,394 --> 00:08:16,895 of the New World, 140 00:08:16,929 --> 00:08:18,663 and it was an absolute disaster. 141 00:08:27,139 --> 00:08:31,910 NARRATOR: Drawn by remote stone ruins spotted from space... 142 00:08:31,977 --> 00:08:35,947 Jeez, look at the scale of this structure. 143 00:08:35,982 --> 00:08:38,416 geologist Martin Pepper is high 144 00:08:38,451 --> 00:08:41,219 in the barren mountains of Arizona. 145 00:08:41,254 --> 00:08:43,722 This is monumental. 146 00:08:44,957 --> 00:08:48,260 NARRATOR: He believes these are 19th-century fortifications 147 00:08:48,327 --> 00:08:50,562 overlooking a snaking mountain pass, 148 00:08:50,596 --> 00:08:54,699 the most treacherous migrant and mail route in history. 149 00:08:56,335 --> 00:08:58,770 It's in the perfect strategic position to 150 00:08:58,938 --> 00:09:01,506 protect anybody trying to safely pass through here. 151 00:09:04,577 --> 00:09:07,279 But protect them from what? 152 00:09:09,949 --> 00:09:13,051 Pepper seeks answers in the area around the ruins. 153 00:09:14,053 --> 00:09:15,086 Look at this. 154 00:09:16,589 --> 00:09:19,457 Looks like some sort of a cemetery or something. 155 00:09:21,794 --> 00:09:24,262 NARRATOR: The century-old cemetery may hold 156 00:09:24,297 --> 00:09:27,432 clues about the immense mountain structure. 157 00:09:27,499 --> 00:09:30,702 PEPPER: Colonel Stone, 158 00:09:30,770 --> 00:09:33,371 John Slater, killed by Apaches. 159 00:09:35,041 --> 00:09:38,543 Killed by Indians in the Apache pass. 160 00:09:38,578 --> 00:09:41,947 This is literally right in the middle of Apache territory. 161 00:09:44,050 --> 00:09:46,184 NARRATOR: The formidable Apache control 162 00:09:46,251 --> 00:09:49,921 a 30,000-square-mile territory around the site in 163 00:09:49,989 --> 00:09:51,256 the satellite image. 164 00:09:52,558 --> 00:09:57,696 After five centuries of peace, they are drawn into war. 165 00:09:57,730 --> 00:10:01,232 In the 1730s, the Apache came into conflict with 166 00:10:01,267 --> 00:10:04,536 the Spanish, who were seeking to expand their landholdings 167 00:10:04,603 --> 00:10:05,904 in Mexico. 168 00:10:05,938 --> 00:10:07,706 Their raids against the Spanish 169 00:10:07,773 --> 00:10:10,175 were both savage and calculated. 170 00:10:13,012 --> 00:10:16,514 NARRATOR: Between 1771 and 1776, 171 00:10:16,549 --> 00:10:19,618 the Apaches slay 1,600 Spaniards 172 00:10:19,685 --> 00:10:22,320 and steal 68,000 animals. 173 00:10:23,522 --> 00:10:25,523 They were one of the first groups to 174 00:10:25,558 --> 00:10:30,996 fully adopt the horse and become horseback warriors. 175 00:10:31,030 --> 00:10:35,133 NARRATOR: Spanish horses and guns empower the Apache. 176 00:10:35,167 --> 00:10:36,034 [gun cocks] 177 00:10:36,101 --> 00:10:37,902 Hardened by battles and betrayal, 178 00:10:37,970 --> 00:10:40,572 they defend their land ferociously. 179 00:10:40,639 --> 00:10:44,209 The Apache became so dangerous that it was just 180 00:10:44,243 --> 00:10:49,180 too difficult for people to pass through the mountains. 181 00:10:50,916 --> 00:10:53,618 Passage is vital for the Butterfield Mail Company, 182 00:10:53,686 --> 00:10:57,088 who, in 1858, 183 00:10:57,123 --> 00:11:00,458 broker a truce with Cochise, an Apache leader 184 00:11:00,526 --> 00:11:03,995 renowned for his willingness to embrace white settlers. 185 00:11:05,097 --> 00:11:06,097 BELLINGER: For a few years, 186 00:11:06,132 --> 00:11:08,233 the Apache would allow the postal workers 187 00:11:08,267 --> 00:11:10,702 to go through the pass unscathed. 188 00:11:11,837 --> 00:11:13,938 HORTON: Indeed, they even trade commodities 189 00:11:14,006 --> 00:11:16,007 and so forth with the stage coach. 190 00:11:17,410 --> 00:11:20,445 NARRATOR: It's an unrivaled armistice 191 00:11:20,512 --> 00:11:22,447 sadly shattered 192 00:11:22,481 --> 00:11:25,417 on February 3rd, 1861. 193 00:11:26,452 --> 00:11:28,853 Lieutenant Bascom of the U.S. Army 194 00:11:28,888 --> 00:11:31,456 accuses Cochise of kidnapping 195 00:11:31,490 --> 00:11:34,626 an American child, and in fact, he had not. 196 00:11:34,693 --> 00:11:36,695 But this whole event is gonna 197 00:11:36,762 --> 00:11:39,431 end in bloodshed on both sides. 198 00:11:41,067 --> 00:11:44,169 NARRATOR: Much of it at the Battle of Apache Pass. 199 00:11:46,072 --> 00:11:48,506 BELLINGER: The Apache were prepared to fight, 200 00:11:48,574 --> 00:11:51,676 and they had studied American military tactics. 201 00:11:54,346 --> 00:11:58,750 NARRATOR: In July 1862, 500 Apache warriors ambush 202 00:11:58,784 --> 00:12:02,087 U.S. forces led by Captain Thomas L. Roberts. 203 00:12:02,121 --> 00:12:05,223 Roberts retreats to the Butterfield Mail Depot 204 00:12:05,257 --> 00:12:07,192 and readies his secret weapon, 205 00:12:07,259 --> 00:12:10,061 two 12-pound mountain howitzer cannons. 206 00:12:11,097 --> 00:12:14,032 Nothing the Apache had at their disposal could 207 00:12:14,066 --> 00:12:17,135 compete with the massive firepower 208 00:12:17,202 --> 00:12:19,003 possessed by the Americans. 209 00:12:19,071 --> 00:12:21,473 [cannons blasting] 210 00:12:21,540 --> 00:12:24,175 The Apache would have been terrified with these 211 00:12:24,210 --> 00:12:28,246 howitzers that would literally cut them to pieces. 212 00:12:29,515 --> 00:12:33,251 NARRATOR: 63 Apache are slain by howitzer shells. 213 00:12:33,285 --> 00:12:34,419 The rest flee. 214 00:12:35,921 --> 00:12:38,223 The battle is over. 215 00:12:38,290 --> 00:12:40,692 The war has just begun. 216 00:12:43,629 --> 00:12:46,698 CAVELL: What this event triggers is 25 years of 217 00:12:46,766 --> 00:12:50,301 warfare between the U.S. Army and the Apache. 218 00:12:50,369 --> 00:12:54,205 NARRATOR: In 1864, to defend Apache Pass, 219 00:12:54,240 --> 00:12:57,108 the U.S. military establishes the structure 220 00:12:57,176 --> 00:13:00,311 in the satellite image, Fort Bowie. 221 00:13:00,379 --> 00:13:02,747 Fort Bowie will become Ground Zero to 222 00:13:02,782 --> 00:13:05,483 try and deal with this Apache menace. 223 00:13:06,418 --> 00:13:09,254 This was an original window that they then bricked up 224 00:13:09,321 --> 00:13:11,756 and most likely it turned into 225 00:13:11,891 --> 00:13:15,226 a rifle opening to shield the shooter 226 00:13:15,261 --> 00:13:16,795 in case of attackers. 227 00:13:16,962 --> 00:13:19,764 [gunshot and indistinct shouting] 228 00:13:19,865 --> 00:13:23,101 NARRATOR: The war pits U.S. generals against legendary 229 00:13:23,135 --> 00:13:26,004 Apache tactician, Geronimo. 230 00:13:26,972 --> 00:13:31,142 While Geronimo was hugely important to the Apache nation, 231 00:13:31,210 --> 00:13:33,344 he was never actually a chief. 232 00:13:33,412 --> 00:13:35,580 He was known as a shaman. 233 00:13:35,614 --> 00:13:37,215 There were those who believed he had 234 00:13:37,282 --> 00:13:40,418 supernatural powers and couldn't be shot. 235 00:13:40,485 --> 00:13:43,054 NARRATOR: Led by their invincible shaman, 236 00:13:43,088 --> 00:13:45,390 Geronimo's Apache take advantage 237 00:13:45,424 --> 00:13:46,825 of their local knowledge. 238 00:13:46,892 --> 00:13:49,160 JANULIS: They used guerilla warfare tactics, 239 00:13:49,228 --> 00:13:52,397 which means hit and run, retreat back to the mountains, 240 00:13:52,431 --> 00:13:54,499 and then do it again. 241 00:13:57,203 --> 00:13:59,704 ALBERTSON: There was really no quarter on either side. 242 00:13:59,772 --> 00:14:02,106 The United States Army committed 5,000 of 243 00:14:02,140 --> 00:14:05,410 the active duty army to chasing down Geronimo. 244 00:14:07,146 --> 00:14:10,548 NARRATOR: The war claimed tens of thousands of casualties. 245 00:14:13,185 --> 00:14:15,620 The fallen are buried in desert graves 246 00:14:15,654 --> 00:14:17,355 like those by the fort 247 00:14:17,389 --> 00:14:19,057 in the satellite image. 248 00:14:20,226 --> 00:14:22,460 Fletcher, 1880. 249 00:14:24,263 --> 00:14:26,698 Unknown Apache child. 250 00:14:29,501 --> 00:14:32,303 Another Apache child, 1885. 251 00:14:32,338 --> 00:14:37,275 Oh, wow, son of Geronimo himself. 252 00:14:38,377 --> 00:14:39,544 Little Robe. 253 00:14:42,047 --> 00:14:45,183 NARRATOR: In 1886, Geronimo surrenders, 254 00:14:45,217 --> 00:14:48,253 effectively ending the Apache Wars. 255 00:14:48,287 --> 00:14:51,556 After a quarter-century of conflict, 256 00:14:51,623 --> 00:14:55,126 friend and foe rest side by side. 257 00:14:56,228 --> 00:14:59,364 PEPPER: This showed that they came to some sort of truce 258 00:14:59,431 --> 00:15:03,534 to bury them right here in the same cemetery. 259 00:15:05,371 --> 00:15:08,473 NARRATOR: The ruins of Fort Bowie and its cemetery 260 00:15:08,507 --> 00:15:12,810 are reminders of all who fell at Apache Pass 261 00:15:12,845 --> 00:15:16,047 and a stark warning from American history. 262 00:15:17,182 --> 00:15:20,985 What we can see from space was the beginning of the end, 263 00:15:21,053 --> 00:15:25,223 before the Apache were broken and put onto reservations. 264 00:15:25,257 --> 00:15:28,493 And even though it's peaceful and tranquil now, 265 00:15:28,527 --> 00:15:34,532 this place has a long history of bloodshed and unrest. 266 00:15:36,835 --> 00:15:40,338 NARRATOR: Coming up, killer seas. 267 00:15:40,406 --> 00:15:43,942 Whatever has happened here, it's not good. 268 00:15:44,009 --> 00:15:46,010 NARRATOR: And red dawn. 269 00:15:46,078 --> 00:15:51,282 These innocent-looking circles are a key zone of the Cold War. 270 00:15:59,158 --> 00:16:02,593 NARRATOR: October 1st, 2020. 271 00:16:02,661 --> 00:16:04,529 The Landsat 8 satellite scans 272 00:16:04,596 --> 00:16:08,266 the U.S. Eastern Seaboard captures 273 00:16:08,333 --> 00:16:10,134 something bizarre spreading from 274 00:16:10,202 --> 00:16:12,003 South Carolina's coastline. 275 00:16:14,707 --> 00:16:17,342 KOUROUNIS: This image is absolutely shocking. 276 00:16:18,277 --> 00:16:20,478 Typically, the waters off of Winyah Bay, 277 00:16:20,545 --> 00:16:25,516 South Carolina, would be beautiful blue-green, 278 00:16:25,551 --> 00:16:28,219 but it is stained brown. 279 00:16:29,922 --> 00:16:32,490 SZULGIT: This is no small plume. 280 00:16:32,557 --> 00:16:36,728 Whatever is leaking to the ocean is big. 281 00:16:36,795 --> 00:16:39,397 NARRATOR: Something in Winyah Bay estuary 282 00:16:39,431 --> 00:16:41,232 is pumping millions of gallons 283 00:16:41,299 --> 00:16:44,936 of rust-colored water into the Atlantic Ocean. 284 00:16:44,970 --> 00:16:48,539 I think it's safe to say that whatever has happened here, 285 00:16:48,574 --> 00:16:50,308 it's not good. 286 00:16:51,877 --> 00:16:54,479 NARRATOR: Satellite images taken over the Carolinas 287 00:16:54,513 --> 00:16:58,149 two years earlier could offer a clue. 288 00:16:58,183 --> 00:17:02,787 In 2018, tremendous amounts of rainfall caused flooding 289 00:17:02,855 --> 00:17:05,723 that overflowed pig farms, 290 00:17:05,791 --> 00:17:09,994 and there were literally floods of pig manure 291 00:17:10,062 --> 00:17:13,364 leaching out into the nearby watersheds. 292 00:17:13,399 --> 00:17:16,267 NARRATOR: North Carolina's hog farms house 293 00:17:16,334 --> 00:17:18,770 around nine million pigs, 294 00:17:18,837 --> 00:17:22,540 which each pump out around two tons of manure a year. 295 00:17:24,009 --> 00:17:28,246 The 2018 floods create fecal tsunamis 296 00:17:28,280 --> 00:17:29,981 so large they can be seen from space. 297 00:17:30,916 --> 00:17:35,086 A flood of pig manure turned the rivers brown, and it really 298 00:17:35,153 --> 00:17:37,789 bears a striking resemblance to what we're seeing 299 00:17:37,856 --> 00:17:39,424 in this image here. 300 00:17:41,393 --> 00:17:43,961 NARRATOR: Yet what puzzles analysts is that there are 301 00:17:44,029 --> 00:17:47,899 reports of similar plumes dating back many centuries. 302 00:17:47,966 --> 00:17:52,003 They are often referred to as blackwater. 303 00:17:52,037 --> 00:17:55,440 The long history of people recording this blackwater 304 00:17:55,507 --> 00:17:57,975 tell us that it predates industrial pollution, 305 00:17:58,043 --> 00:18:00,044 so that's probably not the cause of it. 306 00:18:02,948 --> 00:18:06,017 NARRATOR: What's more, the historical reports claim 307 00:18:06,051 --> 00:18:08,252 that the noxious-looking waters possess strange 308 00:18:08,320 --> 00:18:09,520 healing properties. 309 00:18:09,554 --> 00:18:12,390 SZULGIT: They say that drinking in and bathing in 310 00:18:12,457 --> 00:18:16,194 this water actually helped with their condition. 311 00:18:16,261 --> 00:18:18,896 NARRATOR: The first accounts of blackwater date 312 00:18:18,931 --> 00:18:21,432 to as far back as 1526. 313 00:18:21,467 --> 00:18:25,770 HORTON: A Spanish pioneer settler called 314 00:18:25,904 --> 00:18:27,505 Vazquez de Ayllon 315 00:18:27,539 --> 00:18:31,442 arrived with over 500 fellow Spaniards, 316 00:18:31,477 --> 00:18:33,377 and they planted a colony 317 00:18:33,412 --> 00:18:35,780 close to the mouth of the river. 318 00:18:37,149 --> 00:18:39,283 SZULGIT: When we think of the difficult conditions 319 00:18:39,351 --> 00:18:40,518 that early settlers faced, 320 00:18:40,552 --> 00:18:42,553 we think of them freezing to death in the winter 321 00:18:42,621 --> 00:18:44,989 or having battles with indigenous peoples. 322 00:18:45,023 --> 00:18:49,427 But really, the most dangerous thing they faced was disease. 323 00:18:51,997 --> 00:18:55,266 NARRATOR: During the age of discovery, disease is 324 00:18:55,300 --> 00:18:58,669 the principal cause of death among sailors and settlers. 325 00:18:58,703 --> 00:19:03,975 Scurvy alone kills two million, typhus, typhoid, and dysentery, 326 00:19:04,042 --> 00:19:05,710 countless others. 327 00:19:05,777 --> 00:19:09,747 Back then, sailors would have been in these terribly septic, 328 00:19:09,781 --> 00:19:12,483 horrible conditions where disease would be rife by 329 00:19:12,518 --> 00:19:15,153 the time they arrived on their vessels. 330 00:19:15,187 --> 00:19:18,089 NARRATOR: For the Spanish settlers in 16th-century 331 00:19:18,123 --> 00:19:23,261 South Carolina, locating a clean water supply is critical, 332 00:19:23,295 --> 00:19:26,030 but the state's fetid waterways are 333 00:19:26,064 --> 00:19:29,167 a petri dish of bugs and possible infections. 334 00:19:31,270 --> 00:19:32,770 Not only 335 00:19:32,804 --> 00:19:35,840 does it provide contaminated water sources, 336 00:19:35,874 --> 00:19:39,810 but also becomes a breeding ground for mosquito that can 337 00:19:39,878 --> 00:19:43,414 spread diseases such as malaria and dengue fever. 338 00:19:45,050 --> 00:19:47,652 NARRATOR: Faced with this onslaught 339 00:19:47,686 --> 00:19:49,587 of waterborne horrors, 340 00:19:49,621 --> 00:19:52,456 the Spaniards find sanctuary in the blackwater 341 00:19:52,491 --> 00:19:54,325 seen from space. 342 00:19:54,359 --> 00:19:56,527 When we look at where the water feeding into this 343 00:19:56,562 --> 00:19:58,529 river comes from, it's passing through 344 00:19:58,564 --> 00:20:00,431 a lot of swamps and wetlands, 345 00:20:00,498 --> 00:20:02,433 so it's gonna be interacting with a lot of 346 00:20:02,500 --> 00:20:03,768 decaying plant matter, 347 00:20:03,902 --> 00:20:07,038 and that's going to make it pick up certain things. 348 00:20:08,106 --> 00:20:09,507 NARRATOR: As the rivers move through 349 00:20:09,574 --> 00:20:12,310 forests and wetlands towards the sea, 350 00:20:12,377 --> 00:20:14,412 rotting plant matter leeches tannins 351 00:20:14,446 --> 00:20:18,182 and organic molecules called phenols into the water. 352 00:20:18,250 --> 00:20:21,919 All these natural compounds in the water basically 353 00:20:21,987 --> 00:20:24,055 make it self-sterilizing, 354 00:20:24,122 --> 00:20:28,659 allowing it to be very safe to drink. 355 00:20:29,995 --> 00:20:32,730 NARRATOR: The healing properties of blackwater helped 356 00:20:32,797 --> 00:20:34,198 the South Carolina colonists 357 00:20:34,266 --> 00:20:36,968 to establish the first European settlement on 358 00:20:37,002 --> 00:20:38,569 the continental United States, 359 00:20:39,771 --> 00:20:42,440 but their stay is short-lived. 360 00:20:42,474 --> 00:20:45,042 The minute this settlement gets to shore, 361 00:20:45,077 --> 00:20:47,845 everything goes wrong -- Their supply ship grounds 362 00:20:47,879 --> 00:20:50,881 and cuts off their means of escape, their lifeline. 363 00:20:50,949 --> 00:20:53,718 They rapidly run out of food and resources, because they 364 00:20:53,752 --> 00:20:57,088 don't know the landscape and the colonists 365 00:20:57,155 --> 00:20:59,323 start dying of starvation. 366 00:21:02,794 --> 00:21:04,695 NARRATOR: A month after their arrival, 367 00:21:04,763 --> 00:21:08,165 the Spanish flee, and their settlement is swallowed by 368 00:21:08,233 --> 00:21:09,433 the swamp. 369 00:21:09,501 --> 00:21:11,902 It was the first attempt to settle the shores 370 00:21:11,970 --> 00:21:16,440 of the New World, and it was an absolute disaster. 371 00:21:16,508 --> 00:21:20,478 NARRATOR: Five centuries later, a hurricane hits the site of 372 00:21:20,512 --> 00:21:22,113 the Spanish colony, 373 00:21:22,180 --> 00:21:25,149 generating the giant plume of blackwater captured 374 00:21:25,183 --> 00:21:26,951 from the skies. 375 00:21:26,985 --> 00:21:30,221 As it spreads across the Atlantic, 376 00:21:30,255 --> 00:21:33,591 it prevents sunlight from penetrating the ocean, 377 00:21:33,658 --> 00:21:38,429 leading to a mass die-off in the depths below. 378 00:21:38,463 --> 00:21:40,097 SZULGIT: It's ironic that the dark water 379 00:21:40,132 --> 00:21:42,500 that we see in the satellite image 380 00:21:42,534 --> 00:21:44,068 that would have been a calling card 381 00:21:44,135 --> 00:21:47,071 to early settlers for health and invigoration 382 00:21:47,138 --> 00:21:49,774 turned out to be death to the oceans 383 00:21:49,841 --> 00:21:51,442 hundreds of years later. 384 00:21:59,117 --> 00:22:03,020 NARRATOR: Coming up, setting fire to runways. 385 00:22:03,055 --> 00:22:04,588 Hey, in wartime, you're gonna 386 00:22:04,656 --> 00:22:07,258 try pretty much anything to be effective. 387 00:22:07,292 --> 00:22:10,728 NARRATOR: And the city that enraged Genghis Khan. 388 00:22:10,796 --> 00:22:13,097 This was obviously a very bad decision. 389 00:22:21,173 --> 00:22:24,675 NARRATOR: February 11th, 2020, 390 00:22:24,743 --> 00:22:28,279 478 miles above southwestern England, 391 00:22:28,313 --> 00:22:32,316 a satellite captures this image. 392 00:22:32,384 --> 00:22:34,552 What you've got here is an airfield, 393 00:22:34,586 --> 00:22:36,253 that much is obvious. 394 00:22:36,321 --> 00:22:38,022 But then when you look at it a little bit more closely, 395 00:22:38,056 --> 00:22:41,759 you realize there's something very, very unusual indeed. 396 00:22:41,827 --> 00:22:45,363 There's a bunch of circles and also rectangles, 397 00:22:45,397 --> 00:22:48,766 and what's interesting is there's a great deal of 398 00:22:48,900 --> 00:22:52,136 precision to the shape and the placement of them. 399 00:22:52,203 --> 00:22:54,605 NARRATOR: Each of the mysteries shapes 400 00:22:54,672 --> 00:22:58,442 is around 400 feet in diameter. 401 00:22:58,477 --> 00:23:02,279 It also looks like there's no sign of life. 402 00:23:02,347 --> 00:23:06,751 So if this was active, it must have been decades ago. 403 00:23:09,087 --> 00:23:12,089 NARRATOR: Analysts turned to local land registry documents 404 00:23:12,157 --> 00:23:13,758 for clues. 405 00:23:13,892 --> 00:23:18,295 Looking at the records, this is St. Eval, 406 00:23:18,363 --> 00:23:21,799 an RAF coastal command station from the Second World War, 407 00:23:21,967 --> 00:23:27,304 very active from 1938 to 1945. 408 00:23:27,372 --> 00:23:31,609 NARRATOR: The airbase is one of 444 airfields 409 00:23:31,643 --> 00:23:33,778 the British build during World War II, 410 00:23:33,879 --> 00:23:36,914 with enough combined runway to stretch 411 00:23:36,981 --> 00:23:39,517 from New York to Hong Kong. 412 00:23:41,987 --> 00:23:44,221 PAVELEC: The base is close to the coast, 413 00:23:44,256 --> 00:23:46,590 so it was given the orders of finding 414 00:23:46,658 --> 00:23:49,460 and destroying German submarines out in the water. 415 00:23:49,527 --> 00:23:52,997 NARRATOR: Over the course of the war, 416 00:23:53,064 --> 00:23:56,967 hunter-killer aircraft from the base helped destroy over 417 00:23:57,002 --> 00:23:58,803 200 U-boats threatening 418 00:23:58,970 --> 00:24:02,606 American lives and Allied supplies. 419 00:24:02,674 --> 00:24:04,942 Yet, as they return from their missions, 420 00:24:05,009 --> 00:24:09,313 many pilots encounter an unexpected and deadly threat. 421 00:24:09,347 --> 00:24:13,551 Basically, England's got this dual problem of heavy fog 422 00:24:13,618 --> 00:24:16,287 and then a lot of industrial waste 423 00:24:16,354 --> 00:24:19,156 coming up in clouds from the factories, 424 00:24:19,224 --> 00:24:22,259 and those two combined and make almost, like, 425 00:24:22,294 --> 00:24:26,163 a pea soup that pilots could not see to land in. 426 00:24:28,066 --> 00:24:30,901 NARRATOR: The clouds of dense fog and smog, 427 00:24:30,969 --> 00:24:33,204 which envelope wartime Britain, 428 00:24:33,238 --> 00:24:36,006 claimed the lives of numerous pilots. 429 00:24:37,275 --> 00:24:39,610 They force Prime Minister Winston Churchill 430 00:24:39,644 --> 00:24:41,579 to develop an extraordinary solution, 431 00:24:41,646 --> 00:24:46,584 one that could explain the weird shapes in the image. 432 00:24:46,651 --> 00:24:48,118 WALTERS: What the scientists come up with is 433 00:24:48,186 --> 00:24:51,155 this ingenious idea, and it's called FIDO. 434 00:24:51,189 --> 00:24:52,890 Now, FIDO is not a big dog. 435 00:24:52,924 --> 00:24:54,325 What FIDO stands for is 436 00:24:54,392 --> 00:24:58,729 Fog Investigation and Dispersal Operation. 437 00:24:58,797 --> 00:25:04,401 The idea is to run pipes on either side of the runway 438 00:25:04,469 --> 00:25:09,240 and then flush them with fuel that ignites, and so it 439 00:25:09,274 --> 00:25:11,909 basically illuminates the runway, 440 00:25:11,943 --> 00:25:14,545 enabling the pilots to land safely. 441 00:25:16,481 --> 00:25:18,749 NARRATOR: The infernos generated by burning 442 00:25:18,817 --> 00:25:22,253 120,000 gallons of fuel an hour 443 00:25:22,287 --> 00:25:26,790 also help to disperse thick fog above the runway. 444 00:25:26,925 --> 00:25:29,059 PAVELEC: It seems a little counterintuitive 445 00:25:29,093 --> 00:25:30,494 to set fires along 446 00:25:30,562 --> 00:25:33,163 the side of the runway where you're trying to land, 447 00:25:33,197 --> 00:25:34,565 but hey, in wartime, you're gonna 448 00:25:34,632 --> 00:25:36,634 try pretty much anything to be effective. 449 00:25:38,169 --> 00:25:41,438 NARRATOR: Between 1943 and 1945, 450 00:25:41,506 --> 00:25:43,507 the FIDO system saves the lives 451 00:25:43,575 --> 00:25:46,577 of 10,000 British and American aircrews. 452 00:25:48,079 --> 00:25:51,048 But closer analysis reveals the mystery shapes 453 00:25:51,082 --> 00:25:54,418 aren't connected to this fiery flight safety system. 454 00:25:55,587 --> 00:25:57,154 MUNOZ: If you zoom in, and you look at 455 00:25:57,221 --> 00:25:58,489 the center of these circles, 456 00:25:58,556 --> 00:26:01,158 you see sort of an antenna-type structure. 457 00:26:02,994 --> 00:26:05,296 NARRATOR: Declassified military files confirm 458 00:26:05,363 --> 00:26:08,232 that these are transmitter stations, 459 00:26:08,299 --> 00:26:10,234 ones that played a vital role in 460 00:26:10,301 --> 00:26:13,137 events that unfolded after World War II. 461 00:26:14,139 --> 00:26:16,407 In the immediate aftermath of the Second World War, 462 00:26:16,441 --> 00:26:20,077 the United Kingdom was in a very difficult position. 463 00:26:20,111 --> 00:26:22,846 It had prevailed in the victory, 464 00:26:22,914 --> 00:26:26,350 but the economy was devastated. 465 00:26:28,253 --> 00:26:31,021 NARRATOR: Britain's role in the Allied victory in World War II 466 00:26:31,056 --> 00:26:34,058 cost the nation around $1 trillion 467 00:26:34,125 --> 00:26:37,328 and leaves its industries and defenses in ruins. 468 00:26:39,864 --> 00:26:42,700 As the Cold War dawns, this makes it highly 469 00:26:42,801 --> 00:26:47,004 vulnerable to an attack from its former ally, Russia. 470 00:26:48,440 --> 00:26:49,974 There was a period of time that we thought 471 00:26:50,008 --> 00:26:51,742 that World War III was going to begin in 472 00:26:51,809 --> 00:26:54,745 Berlin and that it was going to continue with an all-out 473 00:26:54,812 --> 00:26:57,314 Soviet attack on the United Kingdom. 474 00:26:57,349 --> 00:27:00,751 [people shouting] 475 00:27:00,819 --> 00:27:04,188 NARRATOR: Fearing a possible communist invasion, 476 00:27:04,222 --> 00:27:07,391 the U.S. dramatically ramps up its military presence 477 00:27:07,425 --> 00:27:09,059 in Britain, 478 00:27:09,094 --> 00:27:11,929 including at an airbase to the south of the site 479 00:27:11,963 --> 00:27:13,263 in the image. 480 00:27:14,366 --> 00:27:18,035 At any given time during the Cold War, there would have 481 00:27:18,102 --> 00:27:20,471 been thousands of U.S. troops, 482 00:27:20,505 --> 00:27:23,440 and not just the troops, but the aircraft 483 00:27:23,508 --> 00:27:25,309 and the weapons capability 484 00:27:25,376 --> 00:27:28,078 should there be some kind of conflict. 485 00:27:29,848 --> 00:27:31,649 NARRATOR: Much like during World War II, 486 00:27:31,716 --> 00:27:35,586 perhaps the greatest threat to peace comes from submarines. 487 00:27:35,653 --> 00:27:39,990 During the Cold War, the Russians build around 488 00:27:40,058 --> 00:27:43,494 1,450 subs and have the largest, 489 00:27:43,528 --> 00:27:45,696 most powerful fleet in the world. 490 00:27:46,998 --> 00:27:49,333 To track this menace, the U.S. 491 00:27:49,400 --> 00:27:52,770 and Britain turn to the Hawker Siddeley Nimrod, 492 00:27:52,837 --> 00:27:54,972 a passenger jet modified for 493 00:27:55,006 --> 00:27:58,008 clandestine maritime surveillance. 494 00:27:58,076 --> 00:28:00,611 The Nimrod was an incredibly interesting 495 00:28:00,645 --> 00:28:01,478 aircraft -- essentially, 496 00:28:01,546 --> 00:28:04,014 it was like the Swiss army knife. 497 00:28:04,082 --> 00:28:06,083 It could be equipped with weapons, 498 00:28:06,150 --> 00:28:09,787 torpedoes, or for intelligence, surveillance, 499 00:28:09,854 --> 00:28:12,456 and reconnaissance operations. 500 00:28:12,490 --> 00:28:15,526 NARRATOR: With a range of almost 6,000 miles, 501 00:28:15,560 --> 00:28:19,930 Nimrods relentlessly comb the ocean for Russian subs, 502 00:28:19,964 --> 00:28:22,733 relaying critical surveillance data back to the site 503 00:28:22,801 --> 00:28:24,301 in the image. 504 00:28:24,368 --> 00:28:27,104 Pilots are authorized to deploy 505 00:28:27,171 --> 00:28:30,240 B-57 tactical strike nuclear depth bombs 506 00:28:30,308 --> 00:28:33,210 on any intruders into British waters. 507 00:28:35,413 --> 00:28:40,150 If you look at it, you would see basically a passenger jet, 508 00:28:40,185 --> 00:28:43,020 but a passenger jet filled with either high-powered 509 00:28:43,054 --> 00:28:47,458 weaponry or very sophisticated equipment. 510 00:28:47,525 --> 00:28:49,927 NARRATOR: During its 40-year lifespan, 511 00:28:49,994 --> 00:28:53,363 the Nimrod flies countless missions over hostile waters, 512 00:28:53,398 --> 00:28:56,567 helping to repel the Soviet threat. 513 00:28:56,601 --> 00:29:01,572 Today, evidence of its vital yet overlooked role at 514 00:29:01,606 --> 00:29:06,877 the front line of the Cold War remains, visible from space. 515 00:29:06,944 --> 00:29:08,946 WALTERS: These innocent-looking circles 516 00:29:09,013 --> 00:29:13,717 are a really highly protected key zone of the Cold War. 517 00:29:13,752 --> 00:29:16,754 It's one of the most secure places on Earth at the time. 518 00:29:23,428 --> 00:29:27,731 NARRATOR: Coming up, attack of the scourge of God. 519 00:29:27,799 --> 00:29:30,667 If you resisted, no mercy was shown. 520 00:29:31,936 --> 00:29:34,404 NARRATOR: And the $60 billion hoard. 521 00:29:35,540 --> 00:29:36,807 If you're a treasure hunter, 522 00:29:36,908 --> 00:29:39,109 you might want to get out there now. 523 00:29:47,185 --> 00:29:51,221 NARRATOR: August 19th, 2018. 524 00:29:51,256 --> 00:29:56,360 A satellite orbits the Sistan Basin in southern Afghanistan, 525 00:29:56,394 --> 00:29:59,396 140,000 square miles 526 00:29:59,463 --> 00:30:02,633 of some of the most inhospitable terrain on Earth. 527 00:30:02,734 --> 00:30:05,102 KOUROUNIS: In every direction, for hundreds of miles, 528 00:30:05,136 --> 00:30:09,506 there's nothing but emptiness and sand dunes. 529 00:30:10,942 --> 00:30:13,610 NARRATOR: Yet closer analysis reveals mysterious evidence of 530 00:30:13,678 --> 00:30:16,079 human presence in these inaccessible, 531 00:30:16,147 --> 00:30:19,316 Taliban-controlled wastelands. 532 00:30:19,350 --> 00:30:21,251 MORGAN: There's a larger outer circle, 533 00:30:21,286 --> 00:30:22,753 and then a smaller inner circle 534 00:30:22,820 --> 00:30:26,123 with some structures inside of it -- it looks enormous. 535 00:30:27,325 --> 00:30:29,459 NARRATOR: The mystery crumbling edifice covers 536 00:30:29,494 --> 00:30:31,795 two million square feet of desert. 537 00:30:31,896 --> 00:30:33,997 There are no trees, there's no water, 538 00:30:34,032 --> 00:30:36,266 no other signs of habitation, 539 00:30:36,301 --> 00:30:39,236 just this large structure that obviously took a lot 540 00:30:39,303 --> 00:30:42,639 of effort to build in the middle of nowhere. 541 00:30:44,275 --> 00:30:46,977 NARRATOR: Dialing up the magnification reveals 542 00:30:47,044 --> 00:30:49,913 the structure is defended by a series of concentric 543 00:30:49,981 --> 00:30:53,984 walls up to a mile long and 30 feet thick. 544 00:30:55,119 --> 00:30:58,555 Military expert Sam Cavell studies them for clues. 545 00:30:58,590 --> 00:31:01,792 The architecture here is very 546 00:31:01,860 --> 00:31:06,430 reminiscent of Islamic military fort design. 547 00:31:06,464 --> 00:31:09,533 It looks like the kind of structural elements 548 00:31:09,600 --> 00:31:11,101 you would expect to see 549 00:31:11,135 --> 00:31:14,738 in something that dates to about the 13th century. 550 00:31:18,109 --> 00:31:20,410 NARRATOR: It appears the giant desert fort 551 00:31:20,478 --> 00:31:21,945 was designed to defend against 552 00:31:22,013 --> 00:31:25,315 the onslaught of perhaps one of the most dreaded forces in 553 00:31:25,350 --> 00:31:27,384 all human history. 554 00:31:27,418 --> 00:31:29,086 In the 13th century, 555 00:31:29,153 --> 00:31:31,922 one of the greatest threats to this area would have been 556 00:31:31,956 --> 00:31:33,390 the Mongol Empire, 557 00:31:33,424 --> 00:31:36,260 led by one of the most fearsome warriors of all time, 558 00:31:36,294 --> 00:31:37,427 Genghis Khan. 559 00:31:38,863 --> 00:31:42,165 NARRATOR: The Mongols' journey to these deserts begins 560 00:31:42,233 --> 00:31:46,203 in the Central Asian steppes in 1206 A.D. 561 00:31:47,972 --> 00:31:51,808 Mobilizing 100,000 highly trained horseback warriors, 562 00:31:51,910 --> 00:31:57,080 Genghis Khan sweeps west, covering up to 100 miles a day, 563 00:31:57,115 --> 00:31:59,516 conquering all in his path. 564 00:31:59,583 --> 00:32:04,187 Over the next 160 years, he and his descendants slaughter 565 00:32:04,255 --> 00:32:06,223 up to 40 million people, 566 00:32:06,257 --> 00:32:09,459 creating a 12-million-square-mile empire 567 00:32:09,527 --> 00:32:11,929 that stretches from the Pacific in the east 568 00:32:11,996 --> 00:32:14,031 to Poland in the West. 569 00:32:14,065 --> 00:32:17,768 Mongolians were known simply for barbarity. 570 00:32:17,902 --> 00:32:19,736 They were known for moving in and raping, 571 00:32:19,804 --> 00:32:21,738 pillaging, and plundering everything that they could get 572 00:32:21,806 --> 00:32:23,507 their hands on. 573 00:32:25,076 --> 00:32:28,078 1219 A.D., the Mongol Horde, 574 00:32:28,145 --> 00:32:32,282 known as the Scourge of God, reaches Afghanistan, ruled at 575 00:32:32,350 --> 00:32:34,384 the time by the Khwarezmian Empire. 576 00:32:36,354 --> 00:32:39,489 To defeat it, Genghis unleashes the fury of 577 00:32:39,557 --> 00:32:41,692 200,000 soldiers. 578 00:32:43,328 --> 00:32:46,229 The Mongol invasion of Afghanistan was 579 00:32:46,297 --> 00:32:47,998 especially brutal. 580 00:32:48,032 --> 00:32:50,867 JANULIS: He would give quarter to those who submitted 581 00:32:50,902 --> 00:32:52,903 to his army at the beginning, 582 00:32:52,970 --> 00:32:56,340 but if you resisted no mercy was shown. 583 00:32:56,374 --> 00:32:59,943 NARRATOR: In 1221, the Mongols lay siege to 584 00:32:59,945 --> 00:33:02,779 a city to the north of the site in the image. 585 00:33:02,947 --> 00:33:05,315 In the process of the siege, 586 00:33:05,383 --> 00:33:08,618 Genghis Khan's favorite grandson is killed. 587 00:33:08,653 --> 00:33:11,488 Now, this is going to force instant 588 00:33:11,522 --> 00:33:14,157 and absolutely brutal retribution. 589 00:33:15,560 --> 00:33:18,128 KOUROUNIS: This was obviously a very bad decision. 590 00:33:18,195 --> 00:33:21,365 This enraged Genghis Khan. 591 00:33:21,399 --> 00:33:24,301 NARRATOR: To avenge his grandson's death, 592 00:33:24,335 --> 00:33:28,105 Genghis deploys the first heavy gunpowder explosives ever 593 00:33:28,139 --> 00:33:30,707 used in combat to slaughter every man, 594 00:33:30,775 --> 00:33:32,509 woman, and child in the city 595 00:33:33,611 --> 00:33:35,445 and surrounding region. 596 00:33:35,480 --> 00:33:38,348 Khan's wrath knew no bounds. 597 00:33:38,416 --> 00:33:42,252 This city was put to the knife. 598 00:33:42,286 --> 00:33:47,657 Everybody was killed, brutalized, and tortured. 599 00:33:47,692 --> 00:33:49,760 Even to this day, it's known as 600 00:33:49,827 --> 00:33:52,429 the City of Screams after this massacre. 601 00:33:56,000 --> 00:33:59,336 NARRATOR: What puzzles analysts is that the site in 602 00:33:59,370 --> 00:34:03,473 the image appears to have been spared from Genghis's rage. 603 00:34:03,508 --> 00:34:06,476 JANULIS: This fortress continued to seemingly thrive 604 00:34:06,511 --> 00:34:08,045 for hundreds of years after 605 00:34:08,112 --> 00:34:10,781 the surrounding cities and fortresses all fell to 606 00:34:10,848 --> 00:34:12,249 the Mongol threat. 607 00:34:14,485 --> 00:34:18,121 NARRATOR: Studies suggest the key to its survival lies in 608 00:34:18,189 --> 00:34:21,391 its groundbreaking use of concentric defenses called 609 00:34:21,459 --> 00:34:23,126 curtain walls. 610 00:34:23,194 --> 00:34:27,531 This kind of circle fortress is something that the Islamic 611 00:34:27,598 --> 00:34:30,400 armies were the first to perfect. 612 00:34:30,468 --> 00:34:32,936 JANULIS: But each fortified wall around the city 613 00:34:33,004 --> 00:34:35,505 creates a kill zone between the next. 614 00:34:35,540 --> 00:34:40,043 It's like taking over a castle multiple times, 615 00:34:40,078 --> 00:34:43,280 and this was a critical military innovation, 616 00:34:43,347 --> 00:34:45,348 and that may be why this city continued 617 00:34:45,382 --> 00:34:47,717 to flourish when everyone around them did not. 618 00:34:50,221 --> 00:34:53,056 NARRATOR: Some 50 years after the Mongols' invasion 619 00:34:53,091 --> 00:34:54,391 of Afghanistan, 620 00:34:54,425 --> 00:34:57,461 Christian knights are confronted by the same defenses 621 00:34:57,495 --> 00:34:59,396 during the Crusades. 622 00:34:59,430 --> 00:35:02,265 Their bloody encounters lead to a transformation in 623 00:35:02,300 --> 00:35:06,136 the design of forts and castles across the globe. 624 00:35:06,170 --> 00:35:09,272 JANULIS: Because the Crusaders saw just how hard it was 625 00:35:09,307 --> 00:35:12,476 to attack one of these types of fortifications, 626 00:35:12,510 --> 00:35:13,810 they brought it home with them 627 00:35:13,978 --> 00:35:15,278 and started building it themselves. 628 00:35:16,581 --> 00:35:18,348 NARRATOR: Over the following centuries, 629 00:35:18,382 --> 00:35:22,519 castles mimicking the Islamic design spring up across Europe 630 00:35:22,586 --> 00:35:24,254 and beyond. 631 00:35:24,321 --> 00:35:26,189 MORGAN: Ultimately, you will see them 632 00:35:26,257 --> 00:35:28,024 spreading to North America. 633 00:35:28,059 --> 00:35:30,227 You get forts in the United States that are 634 00:35:30,294 --> 00:35:31,862 built during the 19th century 635 00:35:31,929 --> 00:35:37,467 that are the expression of an art that began in Afghanistan. 636 00:35:40,505 --> 00:35:42,973 NARRATOR: Today, the fort that helped to spark 637 00:35:43,007 --> 00:35:44,774 this extraordinary revolution 638 00:35:44,909 --> 00:35:48,145 in military architecture worldwide is being swallowed 639 00:35:48,212 --> 00:35:50,013 by the desert. 640 00:35:50,080 --> 00:35:54,618 But for now, its secrets are still visible from space. 641 00:35:55,586 --> 00:35:59,022 It's fascinating that with the most modern technology 642 00:35:59,090 --> 00:36:00,524 available to us, we can look down 643 00:36:00,558 --> 00:36:03,093 and see this thing that tells us so much 644 00:36:03,194 --> 00:36:05,629 about who we are today and where we came from. 645 00:36:12,470 --> 00:36:16,606 NARRATOR: Coming up, hunting shipwrecks from space. 646 00:36:16,641 --> 00:36:20,143 It's easier to identify massive holes 647 00:36:20,178 --> 00:36:21,678 with hidden treasure. 648 00:36:27,418 --> 00:36:29,853 Every day for five decades, 649 00:36:29,920 --> 00:36:34,124 NASA's Landsat program has been scanning our planet, 650 00:36:34,191 --> 00:36:36,793 mapping its constantly evolving surface. 651 00:36:38,930 --> 00:36:42,566 As one of the space agency's satellites travels over 652 00:36:42,600 --> 00:36:45,535 a patch of sea to the north of Belgium, 653 00:36:45,603 --> 00:36:48,205 it captures something that doesn't make sense. 654 00:36:49,473 --> 00:36:53,076 FANARA: What we're seeing here is vast ocean, 655 00:36:53,143 --> 00:36:56,313 and we're also seeing wakes from boats. 656 00:36:56,347 --> 00:36:58,181 But then if you look in the middle, 657 00:36:58,216 --> 00:37:01,418 there are these trails with no vessel 658 00:37:01,452 --> 00:37:04,120 attached, like phantom wakes. 659 00:37:06,857 --> 00:37:11,394 NARRATOR: The ghostly trails are almost three miles long. 660 00:37:11,429 --> 00:37:14,464 CAVELL: There's got to be something sizable under 661 00:37:14,498 --> 00:37:17,534 the water that is creating this disturbance 662 00:37:17,568 --> 00:37:19,803 so that we can see it from satellite images. 663 00:37:25,943 --> 00:37:28,245 NARRATOR: Marine scientists head to the location 664 00:37:28,312 --> 00:37:32,048 and study the seabed using multi-beam sonar. 665 00:37:33,985 --> 00:37:35,919 MORGAN: These are images of the sea floor 666 00:37:35,986 --> 00:37:37,287 and they shoot right through all that silt 667 00:37:37,321 --> 00:37:39,556 and sediment to reveal what's actually going on, 668 00:37:39,590 --> 00:37:42,292 and it appears that there is 669 00:37:42,393 --> 00:37:45,562 a nest of shipwrecks in this position. 670 00:37:48,032 --> 00:37:51,334 FANARA: What is happening here is that the currents moving 671 00:37:51,402 --> 00:37:54,104 around these ships are causing the sediment 672 00:37:54,138 --> 00:37:56,306 to come to the surface. 673 00:38:00,945 --> 00:38:03,580 NARRATOR: From the Phoenicians, through to the Romans 674 00:38:03,614 --> 00:38:06,483 and Vikings, the waters around the wrecks 675 00:38:06,550 --> 00:38:09,653 witnessed trade and warfare throughout antiquity. 676 00:38:11,122 --> 00:38:13,590 But closer analysis suggests these wrecks 677 00:38:13,624 --> 00:38:16,192 are casualties of more recent history. 678 00:38:16,227 --> 00:38:19,963 WALTERS: If they were sunk, you know, before that, 679 00:38:20,030 --> 00:38:23,566 the boats weren't made out of metal, so they rotted away. 680 00:38:23,634 --> 00:38:27,270 CAVELL: One of the vessels is broken completely in half. 681 00:38:27,305 --> 00:38:30,707 I mean, there is some really violent action that has 682 00:38:30,775 --> 00:38:33,710 taken place on this ship, and the question is what? 683 00:38:34,845 --> 00:38:36,746 NARRATOR: Analysts cross-reference the wrecks' 684 00:38:36,781 --> 00:38:40,917 locations with 20th-century maritime records. 685 00:38:40,984 --> 00:38:44,854 PAVELEC: It turns out that these two ships are American 686 00:38:44,922 --> 00:38:46,056 Liberty ships, 687 00:38:46,123 --> 00:38:50,226 the Samsip and the Samvern, that were sunk during 688 00:38:50,261 --> 00:38:51,795 the Second World War. 689 00:38:57,034 --> 00:39:00,203 NARRATOR: Liberty ships were a class of wartime cargo 690 00:39:00,237 --> 00:39:04,107 vessel and a lifeline between America and her allies 691 00:39:04,175 --> 00:39:07,077 during the darkest days of the conflict. 692 00:39:07,144 --> 00:39:11,047 The Liberty ship was a reflection of the exigencies 693 00:39:11,082 --> 00:39:12,315 of the war effort. 694 00:39:12,350 --> 00:39:15,051 They had to be made quick, and they didn't have to 695 00:39:15,086 --> 00:39:16,753 last forever. 696 00:39:16,821 --> 00:39:18,521 WALTERS: They were known as the ugly ducklings, 697 00:39:18,556 --> 00:39:20,457 because they weren't pretty -- It didn't matter. 698 00:39:20,491 --> 00:39:22,459 They got the job done. 699 00:39:22,493 --> 00:39:25,295 NARRATOR: The Liberty ship program was one of 700 00:39:25,362 --> 00:39:29,899 the most astonishing feats of engineering in military history. 701 00:39:29,967 --> 00:39:32,969 Between 1941 and 1945, 702 00:39:33,003 --> 00:39:35,238 18 shipyards across the U.S. 703 00:39:35,305 --> 00:39:37,974 churn out almost 3,000 of these crafts, 704 00:39:39,477 --> 00:39:42,445 each capable of carrying 10,000 tons of 705 00:39:42,513 --> 00:39:45,148 vital supplies to a war-torn Europe. 706 00:39:47,051 --> 00:39:49,486 Part of the hull was poured concrete, 707 00:39:49,520 --> 00:39:51,521 which made it a really quick turnaround 708 00:39:51,588 --> 00:39:53,590 to actually construct these ships. 709 00:39:54,892 --> 00:39:56,459 WALTERS: They were producing these ships 710 00:39:56,527 --> 00:40:00,563 in a matter of hours -- That's extraordinary. 711 00:40:00,598 --> 00:40:02,899 NARRATOR: Yet these workhorses of war 712 00:40:02,933 --> 00:40:06,336 are also virtually defenseless, and many ships 713 00:40:06,403 --> 00:40:09,406 and their crews don't survive the conflict. 714 00:40:09,473 --> 00:40:12,242 These Liberty boats were quite slow 715 00:40:12,276 --> 00:40:14,144 and incredibly hard to maneuver. 716 00:40:14,211 --> 00:40:16,212 So at the end of the day, 717 00:40:16,280 --> 00:40:20,717 these ugly ducklings actually ended up being sitting ducks. 718 00:40:20,751 --> 00:40:24,454 CAVELL: More than 200 would actually be sunk. 719 00:40:24,488 --> 00:40:27,223 But ultimately, more Liberty ships are 720 00:40:27,291 --> 00:40:29,426 produced than the Germans can sink. 721 00:40:29,493 --> 00:40:31,728 And so this is the key to victory. 722 00:40:33,764 --> 00:40:36,466 A discovery of the remains of two lost 723 00:40:36,500 --> 00:40:39,969 Liberty ships is of great interest to historians. 724 00:40:40,037 --> 00:40:42,305 But the satellite image has 725 00:40:42,372 --> 00:40:45,575 a much greater significance than that. 726 00:40:45,642 --> 00:40:50,380 MUNOZ: These sort of trails or plumes in the middle of 727 00:40:50,447 --> 00:40:53,516 the ocean are red flags that could indicate 728 00:40:53,584 --> 00:40:55,452 a shipwreck underneath. 729 00:40:55,519 --> 00:40:58,521 This could really help governments and authorities 730 00:40:58,589 --> 00:41:00,690 identify other shipwrecks 731 00:41:00,758 --> 00:41:03,960 that could be scattered across the world's oceans. 732 00:41:03,994 --> 00:41:06,196 NARRATOR: There are an estimated three million 733 00:41:06,263 --> 00:41:09,732 shipwrecks spread across the ocean floors. 734 00:41:09,800 --> 00:41:12,469 Until now, the resting place of many 735 00:41:12,536 --> 00:41:15,305 of these vessels has been a mystery. 736 00:41:15,372 --> 00:41:17,106 CAVELL: It's a needle in a haystack 737 00:41:17,141 --> 00:41:20,210 operation to try and locate shipwrecks. 738 00:41:20,277 --> 00:41:24,147 But the satellites can look down all day long, any day 739 00:41:24,214 --> 00:41:27,383 they need to, and they can recognize these plumes. 740 00:41:28,519 --> 00:41:30,520 NARRATOR: What intrigues many isn't just 741 00:41:30,554 --> 00:41:32,055 the location of these wrecks, 742 00:41:32,089 --> 00:41:34,157 but what they hold. 743 00:41:34,224 --> 00:41:35,792 Over the years, 744 00:41:35,926 --> 00:41:39,629 around $60 billion dollars of treasure has been claimed by 745 00:41:39,696 --> 00:41:41,397 the ocean depths, 746 00:41:41,432 --> 00:41:46,236 and now, it may be possible to hunt for it from space. 747 00:41:46,303 --> 00:41:50,507 It's really exciting to now realize that we have 748 00:41:50,574 --> 00:41:54,444 a clue into where these shipwrecks might be. 749 00:41:54,511 --> 00:41:56,679 So, if you're a treasure hunter, 750 00:41:56,747 --> 00:41:58,248 might want to get out there now.