The Altiplano Cundiboyacense, with its valleys of Sogamoso-Duitama, Tunja and Ubaté-Chiquinquirá and the southeastern flatlands of the Bogotá savanna, as well as the Tenza Valley to the east, was inhabited for 12,000 years by indigenous peoples. At the arrival of the Spanish conquistadors, the area of approximately was populated by the Muisca, organised in a loose confederation; the Muisca Confederation.