The Great Wall of China: How They REALLY Built It!!

21,196 kilometers. More than half the way around the planet. Built across mountains and deserts, mostly by hand. So how did they actually do it? And why did researchers recently find more than 130 secret doors hidden inside it? In this investigation we uncover why the Great Wall was built, how thousands of crews raised it in record time using earth, stone, reeds and brick, the sticky rice mortar that still holds parts of it together, the hidden doors used by scouts and traders, and life inside a Ming watchtower. Plus: can you really see it from space? ⏱️ CHAPTERS 0:00 Cold open 0:44 Not one wall, but many 2:08 Why build it? 3:16 How they built so fast 5:11 The secret ingredient 6:24 Secret doors and life on the wall 7:56 The verdict 💬 Would you rather have been a builder or a guard on the wall? Tell us in the comments. 🔔 Subscribe for a new history investigation every week. #greatwallofchina #history #ancientchina