Peru contains Machu Picchu, the Inca citadel built in the 15th century in the Andes. The site stands about 2,430 meters above sea level on a mountain ridge near the Urubamba Valley, northwest of Cusco.
Machu Picchu was constructed during the reign of the Inca ruler Pachacuti, who ruled in the 15th century. Its buildings include temples, terraces, residences, and carefully fitted stonework. The site appears to have served a combination of royal, religious, and administrative purposes, although its exact function remains debated.
Spanish colonial records do not appear to mention the citadel, and much of it remained unknown outside the local region until its 1911 promotion by Hiram Bingham. Machu Picchu was declared a UNESCO World Heritage Site in 1983. It is sometimes called the “Lost City of the Incas,” although that phrase more accurately referred to the separate site of Vilcabamba in some historical writing.