In 1911, American archaeologist Hiram Bingham discovered a forgotten ancient city—Machu Picchu—located 120 kilometers north of Cusco, Peru. This ancient city, perched at an altitude of 2,450 meters in the mountains, was built in the 15th century during the reign of Pachacuti Yupanki, the eighth ruler of the Inca Empire. Despite the ravages of time, 216 stone houses and towering granite walls still stand today. These massive walls are constructed from nearly equal-sized stones, laid without mortar yet incredibly sturdy.
The stone masonry techniques of the Incas are astonishing. How did they achieve such mastery without iron tools? The ancient fortress of Sacsayhuamán, located north of Cusco, also showcases this marvel. Its stone walls reach heights of 18 meters, with each massive stone weighing up to 200 tons and measuring about 121 cubic meters. How the Incas quarried and transported such enormous stones remains an unsolved mystery.
