Threads That Speak: How The Inca Used Strings to Communicate | National Geographic
44:41
The Khipu (knot what you think...)
43:25
Unearthed: Mayan City of Blood (S1, E1) | Full Episode
44:25
Cleopatra's Lost Tomb (Full Episode) | Lost Treasures of Egypt
4:54
The Last Incan Bridge | 100 Wonders | Atlas Obscura
8:34
Inca Khipu: The record and writing system made entirely of knots | Curator's Corner S6 Ep9
19:55
Nepal's Mad Honey That Causes Hallucinations (They climb to go insane)
10:08
Inca Knot Numbers - Numberphile
14:11