How Was Machu Picchu Built and Why
Machu Picchu is a royal estate of the Inca Empire built on a saddle between the peaks of Machu Picchu and Huayna Picchu, in the cloud forest of the eastern Andes of Peru, at an elevation of approximately 2,430 meters above sea level. The site is conventionally dated to the mid-fifteenth century and is attributed to the reign of the ninth Sapa Inca, Pachacuti Inca Yupanqui, and his successors, particularly Huayna Capac, in the late fifteenth and early sixteenth centuries. The site is reached by rail from the town of Aguas Calientes and is the most famous and most visited archaeological site in South America. It was declared a UNESCO World Heritage Site in 1983 and is administered as a national archaeological sanctuary by the Peruvian Ministry of Culture.
Location and setting
Machu Picchu is located in the eastern cordillera of the Peruvian Andes, on the eastern slope of the Vilcabamba range, above the bend of the Urubamba River. The site sits on a granite ridge that runs roughly north–south for approximately 1 kilometer and is bounded on the south by a deep cliff above the river, on the east by the peak of Huayna Picchu, and on the west by the peak of Machu Picchu (the “old mountain”). The ridge is geologically unstable, crossed by a series of faults and fractures, and Inca builders integrated the natural features of the site into the design of the buildings and terraces.
The site was largely unknown to the outside world until the North American historian Hiram Bingham, working with the support of Yale University and the National Geographic Society, brought it to international attention in 1911. Bingham was guided to the site by a local farmer, Melchor Arteaga, and his team spent the 1911 and 1912 field seasons clearing and partially reconstructing the site. Bingham’s published accounts, including Inca Land (1922) and Machu Picchu, a Citadel of the Incas (1930), introduced the site to a global audience and established it as the most famous example of imperial Inca architecture.
Dating and historical context
The construction of Machu Picchu is conventionally dated to the period c. 1450 to 1460, during the reign of Pachacuti Inca Yupanqui, although some buildings, particularly in the upper sectors, may have been added during the reigns of Túpac Inca Yupanqui and Huayna Capac. The principal evidence for the dating is the architectural style of the buildings, which is consistent with the late imperial Inca style as documented at Cusco, at Ollantaytambo, and at Choquequirao, and the carbon-14 dating of organic material recovered from the site, which places the construction in the late fifteenth and early sixteenth centuries.
The function of the site is interpreted in light of the surviving buildings and the chronicler traditions. Machu Picchu is conventionally understood to be a royal estate, similar in function to Ollantaytambo and Pisac, dedicated to the cult of the Sapa Inca, the cult of the sun, and possibly the cult of the Apus, the mountain spirits. The chronicler Pedro Sarmiento de Gamboa records that Pachacuti retired to the eastern Andes in the late years of his reign to consolidate his power, and the construction of Machu Picchu may have been part of this consolidation. The site is sometimes identified with the Vilcabamba, the last capital of the Inca resistance to the Spanish, but most modern scholars reject this identification, locating Vilcabamba further to the west, in the tropical lowlands of the Vilcabamba valley.
Construction logistics
The construction of Machu Picchu was a major logistical undertaking. The site is remote, located more than 60 kilometers from Cusco by a difficult mountain road, and the transport of stone, timber, water, and food to the site required the organization of a large labor force. The construction was carried out by the mit’a system, in which communities from across the empire were required to send a proportion of their adult male population to work for the state. The labor force was organized into work parties under the supervision of the camayoc, the master craftsmen, and was provided with food, water, and shelter in temporary camps near the site.
The granite of which the site is built was quarried locally, from outcrops within the site itself. The Inca made use of natural fractures in the granite to detach blocks, and the largest blocks, including the lintels of the Temple of the Sun, were reduced in size and shape using stone hammers, abrasives, and possibly small copper or bronze tools. The finished stones were moved into position by teams of laborers using levers, wooden skids, and log rollers, and were fitted into the walls using the same polygonal techniques documented at Cusco and Ollantaytambo.
The timber used in the construction of the roofs was obtained from the cloud forest, which provided a wide range of species including aliso and chachacomo, and was carried to the site by porters. The construction of the roofs required a separate set of skills, including carpentry, thatching, and the preparation of reed bundles, and the labor force for the roofing was drawn from communities with the relevant experience.
The urban sectors
The site is divided into two main sectors, the Hanan (upper) and the Hurin (lower), each of which is laid out on a series of terraces cut into the mountain flank. The Hanan sector, on the north and west of the site, contained the principal religious and ceremonial buildings, including the Intihuatana stone, the Temple of the Sun, the Room of the Three Windows, the Principal Temple, and the Unfinished Temple. The Hurin sector, on the south and east, contained the principal residential buildings, the storehouses, the workshops, and the houses of the artisans. The two sectors are connected by a sequence of stairways, plazas, and terraces, and the urban plan is integrated with the natural topography of the site.
The site contains approximately 172 buildings, including temples, royal residences, storehouses, workshops, and a series of fountains that channel water from a natural spring above the city. The buildings are constructed in the imperial style, with polygonal walls of closely fitted granite blocks, trapezoidal doorways, and thatched roofs. The largest single building is the Temple of the Sun, a curved polygonal structure built atop a large natural boulder, and the most photographed is the Intihuatana stone, a carved granite outcrop that is believed to have served as an astronomic observation point.