Machu Picchu, Peru

Machu Picchu  is a pre-Columbian 15th-century Inca site located 2,430 metres (7,970 ft) above sea level. It is situated on a mountain ridge above the Urubamba Valley in Peru, 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 the Inca World.

The Incas started building the "estate" around AD 1400 but abandoned it as an official site for the Inca rulers a century later at the time of the Spanish Conquest. Although known locally, it was unknown to the outside world before being brought to international attention in 1911 by the American historian Hiram Bingham. Since then, Machu Picchu has become an important tourist attraction.

Since the site was never known to the Spanish during their conquest, it is highly significant as a relatively intact cultural site. Machu Picchu was declared a Peruvian Historical Sanctuary in 1981 and a UNESCO World Heritage Site in 1983. In 2007, Machu Picchu was voted one of the New Seven Wonders of the World in a worldwide Internet poll.

Machu Picchu was built in the classical Inca style, with polished dry-stone walls. Its three primary buildings are the Intihuatana, the Temple of the Sun, and the Room of the Three Windows. These are located in what is known by archaeologists as the Sacred District of Machu Picchu. In September 2007, Peru and Yale University almost reached an agreement regarding the return of artifacts which Yale has held since Hiram Bingham removed them from Machu Picchu in the early 20th century. In November 2010, a Yale University representative agreed to return the artifacts to a Peruvian university.