In the south of the valley of Cusco, the site of Pikillacta is a remainder of the Huari culture, the great rival of the Incas before their incredible expansion. This site is actually the vestige of a whole city: this one is characterized by the presence of walls and fortifications, notions which did not exist anywhere else in the area at the time. Some of the structures have several floors, and the walls are between 7 and 12 meters high. The city is organized in several districts, but the military dimension is clearly present. Outside the city, the remains of a large aqueduct are visible, which complements the underground irrigation system discovered there. Many mysteries still linger on this site: why it was deserted, how it resisted so well to the onslaught of time... an air of indecipherability that hovers over this abandoned city and quickly arouses the keen interest of all the lucky ones who venture there.