Another interesting historical fact that perhaps saved important details about the Inca civilization is the fact that the Spanish conquerors never found Machu Picchu. While the Spanish were responsible for plundering many other Incan sites, this most sacred site remained a secret. Over the course of centuries, much of the site became overgrown. While it was known by the local people, it wasn't discovered for the rest of the world until 1911 when an 11-year-old boy led Professor Bingham to the site. Bingham called his book about the ruins The Lost City of the Incas-it makes for fascinating reading before a trip to Peru if you want to arrive well versed in the history of Machu Picchu.