Located near Lake Titicaca in western Bolivia, Tiwanaku is a Pre-Columbian archaeological site that was once home to an estimated 10,000 to 20,000 people. Covering around 4 square kilometers, the site is renowned for its decorated ceramics, monumental structures, and megalithic blocks. First written about in 1549 by Spanish conquistador Pedro Cieza de León during a search for the Inca capital of Qullasuyu, it is one of the largest sites in South America.