Black Canyon of the Gunnison National Park, 30,300 acres (12,272 hectares), W central Colorado, in the Rocky Mts. The park embraces the most spectacular stretch of the 53-mi (85-km) long Black Canyon, which is named for the sheer, dark-colored walls carved by the unspoiled Gunnison River. The narrow canyon is so deep (as much as 2,660 ft/811 m) that its bottom is in the shadows for most of the day. At the bottom, ancient Proterozoic rocks are exposed; wildlife in the park includes black bears, cougars, bobcats, golden eagles, peregrine falcons, and swifts. The area was designated a national monument in 1933 and became a national park in 1999.