Dolores River

River in southwest Colorado, U.S., rising in the La Plata Mountains and flowing southwest through deep canyons, past Dolores, then northwest through Paradox Valley, at the north end of which it is met by its chief tributary, the San Miguel River. It continues on past Gateway and across the Utah border to join the Colorado River near Moab after a course of about 250 miles (400 km). Melting