Puma Punku: The Ancient Stones That Still Puzzle Engineers
Quick Facts: Location: Tiwanaku, near Lake Titicaca, Bolivia | Date/Year: Built c. 500-600 CE | Status: Partly solved (builders known, methods debated) | Largest sandstone block: roughly 131 tons The Stone Puzzle at 12,600 Feet: Inside Bolivia's Puma Punku Picture a field of gray and red blocks scattered across the Bolivian Altiplano, each one cut with right angles so crisp they look machined. Some are shaped like the letter H. A few weigh as much as a loaded Boeing 737. Nobody has ever found the instruction manual. The Door of the Puma Puma Punku sits about 3,850 meters (12,600 feet) above sea level, roughly 70 kilometers west of La Paz. The name comes from Aymara and is usually translated as "Door of the Puma." It forms part of the larger Tiwanaku complex, the ceremonial heart of a civilization that dominated the Lake Titicaca basin from around 500 to 1000 CE. UNESCO added Tiwanaku to the World Heritage List in 2000. The Tiwanaku people left no written langua...