It is situated on a mountain ridge above the Sacred Valley which is 80 kilometres (50 mi) northwest of Cuzco 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 mistakenly referred to as the "Lost City of the Incas" (a title more accurately applied to Vilcabamba), it is the most familiar icon of Inca civilization.
The Incas built the estate around 1450, but abandoned it a century later at the time of the Spanish Conquest. Although known locally, it was not known to the Spanish during the colonial period and remained unknown to the outside world before being brought to international attention in 1911 by the American historian Hiram Bingham. Most of the outlying buildings have been reconstructed in order to give tourists a better idea of what the structures originally looked like. By 1976, 30% of Machu Picchu had been restored, restoration continues today.
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 structures are the Inti Watana, the Temple of the Sun, and the Room of the Three Windows.
Machu Picchu was built around 1450, at the height of the Inca Empire. Its construction appears to date to the period of the two great Incas, Pachacutec Inca Yupanqui (1438–71) and Tupac Inca Yupanqui (1472–93). 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 travellers before the Spanish conquistadors arrived in the area. The conquistadors had notes of a place called Piccho, although there is no record of the Spanish having visited the remote city. The types of sacred rocks defaced by the conquistadors in other locations are untouched at Machu Picchu.
Although the citadel is located only about 80 kilometers (50 mi) from Cusco, the Inca capital, the Spanish never found it and so did not plunder or destroy it, as they did many other sites. Over the centuries, the surrounding jungle grew over the site, and few outside the immediate area knew of its existence.
The site may have been discovered and plundered in 1867 by a German businessman, Augusto Berns. There is some evidence that a German engineer, J. M. von Hassel, arrived earlier. Maps found by historians show references to Machu Picchu as early as 1874.
In 1911 Hiram Bingham, an American historian and explorer, travelled the region looking for the old Inca capital and was shown to Machu Picchu by a local farmer. Bingham brought Machu Picchu to international attention and organized another expedition in 1912 to undertake major clearing and excavation. He returned in 1914 and 1915 to continue with excavation.
In 1981, Peru declared an area of 325.92 square kilometres (125.84 sq mi) surrounding Machu Picchu a "Historical Sanctuary". In addition to the ruins, the sanctuary includes a large portion of the adjoining region, rich with the flora and fauna of the Peruvian Yungas and Central Andean wet puna ecoregions.
In 1983, UNESCO designated Machu Picchu a World Heritage Site, describing it as "an absolute masterpiece of architecture and a unique testimony to the Inca civilization".
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