BLACK CANYON OF THE GUNNISON NATIONAL MONUMENT

national monument, comprising a deep, narrow gorge in western Colorado, U.S., 11 miles (18 km) east of Montrose. Established in 1933, the national monument occupies an area of 32 square miles (83 square km). The canyon was cut by the Gunnison River (named for the army engineer John W. Gunnison) and its tributaries. At the section where its walls are steepest, it is 10 miles (16 km) long with depths ranging from 1,730 to 2,425 feet (525 to 750 m), while its rim width narrows to 1,300 feet (400 m) and its floor width to 40 feet (12 m). The Black Canyon derives its name from its black-stained, lichen-covered walls, which accentuate the gloom of the chasm. Roads on the North and South rims, with overlooks and foot trails, reach 8,000 feet (2,400 m) above sea level. Block islands and pinnacles form the canyon's most striking features. The Black Canyon is the habitat of mule deer, coyotes, bobcats, foxes, rock squirrels, and a wide variety of birds, including the golden and bald eagles. Most of the monument has a vegetation cover of Gambel oak and juneberry.