Machu Picchu Valley. He organized the 1911 Yale Peruvian Expedition in part to search for the Inca capital, which was thought to be the city of Vitcos. He consulted Carlos Romero, one of the chief historians in Lima who showed him helpful references and Father Antonio de la Calancha’s Chronicle of the Augustinians. In particular, Ramos thought Vitcos was "near a great white rock over a spring of fresh water." Back in Cusco again, Bingham asked planters about the places mentioned by Calancha, particularly along the Urubamba River. According to Bingham, "one old prospector said there were interesting ruins at Machu Picchu,"
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 The resulting license was soon rescinded.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