The excellent state of preservation of Machu Picchu is due to several circumstances. The Spanish ‘conquistadors’ never reached Machu Picchu and its builders left the city with its completion. (Some researchers even assume that the city was never inhabited.) It seems to have been established that the construction of Machu Picchu began at the earliest in 1438 under Inca Pachacuti and that it was already abandoned a century later.

Machu Picchu (“old summit” in Quechua) is a relatively small Inca city, whose center occupies an area of approximately 770 by 330 meters. The settlement sits on a narrow rock ridge and is surrounded by a wall. Another wall separates the agricultural sector from the residential districts. The overall architectural concept emphasises the segregation of different areas so that the impression of different districts is created. Their number varies according to source or researcher, but a clear division between upper and lower city (hanan or hurin) is discernible. Between them lies a series of open squares and courtyards. Finer masonry can be found in the upper half, while simpler residential buildings dominate in the lower part. Accordingly, those buildings with a special function are also located in the hanan district, such as the “Temple of the Sun” (presumably an observatory) with its curved wall, the “Room of the Three Windows” and the “Main Temple”, which is only bricked on three sides. Machu Picchu’s “Intihuatana” is also located on a small hill on the hanan side, a stone column with a rectangular ground plan on a single-stage platform that merges laterally into the grown rock. This ritual sundial casts practically no shadow at the winter and summer solstice, so that one assumes that it held the sun in a certain way. Since Machu Picchu was never conquered by the Spaniards, the Intihuatana here was not destroyed by them as in other Inca cities. What the Spaniards didn’t achieve was done by a film crew who shot a commercial for a Peruvian beer here in 2001. A heavy camera crane tilted onto the tip of the Intihuatana and damaged it irreparably. Inca priests used these ‘sundials’ to determine the change of seasons and the right time for sowing by comparing the measurement results of different Intihuatanas.

Why the Inca built a city in this specific place of the Urubamba Valley remains unexplained. The fact that the place is easy to defend due to the natural conditions and also features such as the drawbridge and the city wall speak for the theory of a citadel, but there are several comparable settlements on mountain tops in Urubamba Valley. The prominent peak of Huayna Picchu (‘young peak’) may have played a role in the choice of location. In a cave of its northern flank is the so-called “Temple of the Moon”. Underground one finds here finest masonry including a large trapezoidal gate and niches as well as a row of steps carved into the rock. The difficult access and the orientation of the building to a high mountain top suggest that it was an important Inca sanctuary. As in other Inca cities, the terraced area exceeded the needs of the population, estimated at 1000 inhabitants. One theory assumes that around Machu Picchu coca was cultivated on a large scale to meet Cusco’s needs with its endless succession of ceremonies and festivals. The sacred leaves and other useful plants find ideal growing conditions in the warm and humid climate of the surroundings, so it seems obvious that production in Machu Picchu’s fields was mainly for the capital’s market.

Since 2008, one of the legends surrounding the mysterious Inca city seems to have been that Hiram Bingham discovered Machu Picchu. Historians from the USA and Peru assume that as early as 1867 the German entrepreneur Augusto Berns discovered Machu Picchu and plundered it with the approval of the Peruvian government.

Today Machu Picchu is at risk of falling victim to its popularity and its uncontrolled exploitation by the tourism industry. In 1992, 9000 visitors came to Machu Picchu in the whole year, in 2012 it reached almost 1.2 million. Only hesitantly, the Peruvian government bowed to the pressure of UNESCO and other bodies and took measures to clean up the Inca Trail to Machu Picchu and to limit access to 2500 visitors per day. Uncoventionally, the Finnish government has offered Peru the cancellation of a quarter of its debt in exchange for a protection program for Machu Picchu.