The river then dives abruptly into the depths of Westwater Canyon, cutting a tight corridor through shimmering, smooth, fluted black schist. Far above are the bright red walls of the Wingate Sandstone and the cream-colored Entrada Sandstone. The short and riotous journey through Westwater ends in the gentle desert near Cisco. Recreationists flock to the river from April through October. More than 15,000 user-days are recorded annually in Westwater Canyon, and 7,000 in Ruby and Horsethief canyons.
Commercial outfitters offer trips ranging from one to four days in length.
Hikers wander through a maze of twisting tributary canyons, in which perennial streams display plunge pools and waterfalls. Black Ridge Canyons includes innumerable spires and pinnacles, a concentration of natural arches surpassed only by Arches National Park, and a huge 300-foot cavern cut by a stream meander in Mee Canyon. In fact, the Black Ridge Canyons unit is under study by the National Park Service as a potential addition to Colorado National Monument. Biotic Refuge Species of wildlife that have been largely extirpated from native habitat elsewhere have found a home in these river canyons. Golden eagles nest at various sites within the area.