Machu Picchu or Machu Pikchu, old person, pikchu pyramid; mountain or prominence with a broad base which ends in sharp peaks, "old peak", is a 15th-century Inca site located 2,430 metres (7,970 ft) above sea level. It is located in the Cusco Region, Urubamba Province, Machupicchu District in Peru. It is situated on a mountain ridge above the Sacred Valley which is 80 kilometres (50 mi) northwest of Cusco and through which the Urubamba River flows. Most archaeologists believe that Machu Picchu was built as an estate for the Inca emperor Pachacuti (1438–1472). Often referred to as the "Lost City of the Incas", it is perhaps the most familiar icon of Inca civilization.