This Incan citadel was built more than 500 years ago at an elevation of 7,972 feet in the Andes Mountains of central Peru. The site remained unknown to the modern world until 1911 when it was uncovered by American explorer Hiram Bingham. Getting to Machu Picchu requires a scenic train ride or an ambitious hike. Either way, have your cameras ready because this legendary sanctuary and its spectacular setting are stunners. Though not on the Amazon River, many river cruise lines offer trip extensions to see Machu Picchu.