Cañon del Inca, 8km west of Tupiza, makes a great destination for a half-day hike via Quebrada Palmira, a normally dry wash flanked by tall and precarious fin formations. The route leads past the Puerta del Diablo rock formation, 5km outside Tupiza. The right fork of the wash is rather comically known as Valle de los Machos (Valley of Males); the name stems from the clusters of exceptionally phallic pedestal formations.
It's also possible to reach the canyon on a three-hour round trip on horseback.
