Písac or Pisaq s a Peruvian village in the Sacred Valley of the Incas. It is situated on the Willkanuta River. Pisac is most known for its Incan ruins and large market every Sunday, Tuesday, and Thursday, an event which attracts heavy tourist traffic from nearby Cusco.
Pisac is perhaps best known for its Incan ruins, known as Inca Písac, which lie atop a hill at the entrance to the valley. The ruins are separated along the ridge into four groups: P'isaqa, Inti Watana, Qalla Q'asa, and Kinchiraqay Inti Watana group includes the Temple of the Sun, baths, altars, water fountains, a ceremonial platform, and an inti watana, a volcanic outcrop carved into a "hitching post for the Sun" (or Inti). The angles of its base suggest that it served to define the changes of the seasons. Qalla Q'asa, which is built onto a natural spur and overlooks the valley, is known as the citadel. The Inca constructed agricultural terraces on the steep hillside, which are still in use today. They created the terraces by hauling richer topsoil by hand from the lower lands. The terraces enabled the production of surplus food, more than would normally be possible at altitudes as high as 11,000 feet.