Machu Picchu is a pre-Columbian Inca site located 2,430 metres (8,000 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 Cuzco and through which the Urubamba River flows. The river is a partially navigable headwater of the Amazon River. Often referred to as "The Lost City of the Incas", Machu Picchu is one of the most familiar symbols of the Inca Empire.
The Incas started building it around 1460 AD but was abandoned as an official site for the Inca rulers a hundred years later, at the time of the Spanish conquest of the Inca Empire. Although known locally, it was said to have been forgotten for centuries when the site was brought to worldwide attention in 1911 by Hiram Bingham, an American historian. Since then, Machu Picchu has become an important tourist attraction. It has recently come to light that the site may have been discovered and plundered several years previously, in 1867 by a German businessman, Augusto Berns. In fact, there is substantial evidence that a British missionary, Thomas Payne, and a German engineer, J. M. von Hassel, arrived earlier than Hiram, and maps found by historians show references to Machu Picchu as early as 1874.
Machu Picchu was declared a Peruvian Historical Sanctuary in 1981 and a UNESCO World Heritage Site in 1983. Since it was not plundered by the Spanish when they conquered the Incas, it is especially important as a cultural site and is considered a sacred place.