This once was the only entrance to the sacred site of the Incas. Machu Picchu was constructed over the span of about 100 years, and was meants for the elite and nobles- mainly as a training grounds for the nobles' children. When the Spaniards conquered the Incas, they couldn't find Machu Picchu. It was one of the rare sites that was saved from the Conquistadores. The site was 'found' again by Hiram Bingham in 1911. Machu Picchu means 'Old Mountain', or better said, 'Wise Mountain' or 'Mountain of Wisdom'.