Machu Picchu was built around 1450 at the height of the Inca Empire between two mountains near Cuzco, Peru. It may have been a summer city for the King of Cuzco and was abandoned around 1572 due to the Spanish conquest. The Incas crafted the stone structures with such precision that a thin knife cannot fit between the joints, held together through skill rather than mortar. Machu Picchu was lost to the world until 1911 when it was rediscovered and is now one of the New Seven Wonders of the World.