The unfinished temple in a southern valley of the Lake Titicaca Basin in modern-day Bolivia has been a mystery for at least 500 years. Now known as the Pumapunku—”Door of the Jaguar” in the Quechua language—the complex stone structure is part of a sprawling complex of pyramids, plazas, and platforms built by a pre-Columbian culture we now call the Tiwanaku. Construction began around 500 CE and proceeded off and on, in phases, over the next few centuries until the Tiwanaku left the site around 900 or 1000 CE.
When the Inca Empire rose around 1200 CE, they claimed the sprawling ceremonial complex as the site of the world’s creation, although they didn’t finish the Tiwanaku’s temple.
Old school and high tech
Spanish visitors in the 1500s and 1600s describe “a wondrous, though unfinished, building” with walls of H-shaped andesite pieces and massive gateways and windows carved from single blocks. These were set on remarkably smooth sandstone slabs, some of which weighed more than 80 tons. But after centuries of looting, the stones of the Pumapunku are so scattered that not one lies in its original place. The Tiwanaku left behind no written documents or plans to help modern researchers understand what their buildings looked like or what purpose they served.