Machu Picchu is a 15th-century Inca citadel situated on a mountain ridge 2,430 meters above sea level in the Cusco Region of Peru. Built around 1450, it was abandoned a century later during the Spanish Conquest but remained unknown to the outside world until Hiram Bingham brought it to international attention in 1911. The site is famous for its 'ashlar' masonry, where stones are cut so precisely that they fit together without mortar. It includes temples, astronomical observatories, and over 700 agricultural terraces. The Intihuatana stone, a ritual stone associated with the astronomical calendar, is one of its most important features. Recognized as a UNESCO World Heritage site and one of the New Seven Wonders of the World, Machu Picchu provides critical insight into the social, religious, and agricultural sophistication of the Inca Empire.