Lost city Inca site situated on a mountain ridge above the Urubamba Valley in Peru. Often referred to as the "Lost City of the Incas", it is perhaps the most familiar icon of the Inca World. Machu Picchu was built around 1450, at the height of the Inca Empire. It was abandoned just over 100 years later, in 1572, as a belated result of the Spanish Conquest. It is possible that most of its inhabitants died from smallpox introduced by travelers before the Spanish conquistadors arrived in the area. In 1911, Melchor Arteaga led the explorer Hiram Bingham to Machu Picchu, which
Machu Picchu zone exists above the area. UNESCO is considering putting Machu Picchu on its List of World Heritage in Danger. During the 1980s a large rock from Machu Picchu's central plaza was moved to a different location to create a helicopter landing zone. In the 1990s, the government prohibited helicopter landings. In 2006, a Cusco-based company, Helicusco, sought approval for tourist flights over Machu Picchu. The resulting license was soon rescinded. Authorities have struggled to maintain tourist safety. Tourist deaths have been linked to altitude sickness, floods and hiking accidents. UNESCO received criticism for allowing tourists at the location given high