Sacsayhuamán
The massive Inca fortress overlooking Cusco, Sacsayhuamán is one of the greatest architectural achievements of the ancient world. It features enormous zigzag walls built from stones weighing up to 200 tons, fitted together with astonishing precision without mortar. Every year on June 24th, the fortress hosts Inti Raymi, the grand Inca Festival of the Sun that attracts thousands of visitors.