Who discovered it in 1911

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Machu Picchu is one of the seven wonders of the world. It is located in the Cusco Region of Machupicchu District, Peru. The Inca emperor Pachacuti built Machu Picchu as an estate around the year 1450. In the beginning, the site developed as a city. But then it was abandoned a century during the Spanish Conquest. The American explorer Hiram Bingham discovered it in 1911. Machu Picchu is a great representation of the Incan way of life. It attracts explorers all over the world every year.

Question: Who discovered it in 1911?