Among the least understood of ancient megalithic sites in South America is Tiwanaku, located about 12,500 feet in elevation near Lake Titicaca, Bolivia. And even less is known about Puma Punku, which is in fact part of the Tiwanaku complex, and displays levels of stone shaping craftsmanship that can barely be recreated today. Who built these amazing places, when, and why? Brien was featured in an hour long special on Ancient Aliens TV, season 4 discussing both places...or are they one and the same?