Machu Picchu

Machu Picchu is a 15th-century Inca citadel located in southern Peru.

It sits on a mountain ridge in the Eastern Cordillera. The site is in the Machupicchu District of Urubamba Province. It is positioned northwest of Cusco and above the Sacred Valley. The Urubamba River flows below in a deep canyon. This area has a subtropical mountain climate. Many people call it the "Lost City of the Incas." It is a major archaeological site in the Americas. It serves as a powerful symbol of the Inca civilization.

The construction of the site used the classical Inca style. This style features finely crafted dry-stone walls. Dry-stone masonry means stones are fit together without mortar. This technique creates very strong and precise structures. Notable buildings include the Temple of the Sun. There is also the Temple of the Three Windows. Another important feature is the Intihuatana ritual stone.

The site sits on a narrow saddle between two peaks. These peaks are Machu Picchu and Huayna Picchu. In the Quechua language, "Machu" means old and "Picchu" means peak. Therefore, the name often translates to "old mountain."

Archaeologists study the history of the site through different methods. Earlier models suggested construction began around 1450. This was based on the reign of Pachacuti Inca Yupanqui. However, modern radiocarbon dating provides different details. This method measures carbon in organic remains to find ages. A 2021 study used 26 AMS radiocarbon measurements from human remains. This research concluded that people occupied the site from 1420 to 1530. The site was likely a royal estate for Emperor Pachacuti. It was used for roughly 80 years before being abandoned. This abandonment likely happened during the Spanish conquest.

Life at the citadel involved a diverse group of people. It is estimated that about 750 people lived there. Most were support staff who lived there permanently. Other residents included religious specialists and temporary workers. These workers helped with the ruler's well-being and enjoyment. Studies of skeletal remains show the community was very diverse. Genome-wide analyses show people came from many different areas. They had Andean, coastal, Ecuadorian, and Amazonian ancestries. These immigrants lived and were buried together. They brought different diets involving maize, potatoes, grains, and fish. Some moved from coastal areas to the mountain. This change is seen in their diets having more corn.

Engineering was vital for surviving on the steep mountain. The Inca built hundreds of man-made terraces called andenes.

These terraces served several important purposes. They helped stabilize the slopes against landslides and erosion. They also helped manage soil fertility and drainage. Because the area receives over 1,000 mm of rain annually, drainage was critical. The terraces were built in layers for this reason. The bottom layer had large stones and loose gravel. Above that was packed sand and gravel. Finally, rich topsoil was placed on top. This topsoil was likely moved from the valley floor.

Agricultural activity on the terraces was limited. The farming area makes up only about 60% of the land. The crops were mostly corn and potatoes. This was not enough food to support 750 people. Therefore, much of the food was imported from other valleys. People also brought animals to the site for food and use. Most animal bones found were from llamas and alpacas. These animals usually live at higher altitudes called the Puna. Guinea pigs were also found in special tomb caves. They were likely used for meat or funerary rituals. Researchers even found six dogs that served as companions to the dead.

The site was known locally for a long time. The Peruvian explorer Agustín Lizárraga reached it in 1902. He marked his name on a window in charcoal. However, Hiram Bingham III brought it to international attention in 1911.

Since then, its importance has grown globally. Peru named it a National Historic Sanctuary in 1981. In 1983, it became a UNESCO World Heritage Site. In 2007, it was named one of the New Seven Wonders of the World. Today, it is Peru's most visited international destination. Over 1.5 million visitors arrive at the site every year.