Take a tour of Machu Picchu in Peru – part of the World’s Greatest Attractions series by GeoBeats. High in the Peruvian mountains, above the clouds, stands the enchanting city of Machu Picchu. It was built by the Incas in roughly 1450 AD and only rediscovered in 1911. In the interim, it was wiped out by smallpox and civil war within 100 years. Spanish conquistadors never found Machu Picchu, so the city remains comparatively in a good condition. The remarkable architecture of the city is made up of mortarless, but very closely fitted stone blocks. Because of its isolated location, it is theorized that Machu Picchu was a royal retreat. The city, which means "Old Peak", is a scenic jewel of the Inca Empire.