Machu Picchu is a well preserved Pre-Columbian town located on a high mountain ridge above the Urubamba valley in modern-day Peru. It is thought the city was built by the Inca emperor Pachacuti starting in about 1440 and was inhabited until 1532. The city was re-discovered in 1911 by Hiram Bingham. This World Heritage Site is a popular tourist attraction.Photo credit: Chmouel Boudjnah