I
Very narrow, deep valley cut by a river through resistant rock and having steep, almost vertical sides.
Canyons occur most often in arid or semiarid regions. Some canyons (e.g., the Grand Canyon ) are spectacular natural features. See also submarine canyon .
II
[c mediumvioletred] (as used in expressions)
Black Canyon of the Gunnison National Monument
Bryce Canyon National Park
Canyon de Chelly National Monument
Grand Canyon
Grand Canyon series
Hells Canyon
Kings Canyon National Park
submarine canyon
Walnut Canyon National Monument