With a mean average elevation of 6,800 ft (2,074 m), Colorado is the nation's highest state. Dominating the state are the Rocky Mountains. Colorado has 54 peaks 14,000 ft (4,300 m) or higher, including Elbert, the highest in the Rockies at 14,433 ft (4,402 m), and Pikes Peak, at 14,110 ft (4,301 m), one of the state's leading tourist attractions.
The entire eastern third of the state is part of the western Great Plains, a high plateau that rises gradually to the foothills of the Rockies. Colorado's lowest point, 3,350 ft (1,022 m), on the Arkansas River, is located in this plateau region. Running in a ragged north–south line, slightly west of the state's geographic center, is the Continental Divide, which separates the Rockies into the Eastern and Western slopes. The Eastern Slope Front (Rampart) Range runs south from the Wyoming border and just west of Colorado Springs. Also on the Eastern Slope are the Park, Mosquito, Medicine Bow, and Laramie mountains. Western Slope ranges include the Sawatch, Gore, Elk, Elkhead, and William Fork mountains. South of the Front Range, crossing into New Mexico, is the Sangre de Cristo Range, separated from the San Juan Mountains to its west by the broad San Luis Valley. Several glaciers, including Arapahoe, St. Mary's, Andrews, and Taylor, are located on peaks at or near the Continental Divide. Colorado's western region is mostly mesa country—broad, flat plateaus accented by deep ravines and gorges, with many subterranean caves. Running northwest from the San Juans are the Uncompahgre Plateau, Grand Mesa, Roan Plateau, the Flat Tops, and Danforth Hills. The Yampa and Green gorges are located in the northwestern corner of the state.
Blue Mesa Reservoir in Gunnison County is Colorado's largest lake. Six major river systems originate in Colorado: the Colorado River, which runs southwest from the Rockies to Utah; the South Platte, northeast to Nebraska; the North Platte, north to Wyoming; the Rio Grande, south to New Mexico; and the Arkansas and Republican, east to Kansas. Dams on these rivers provide irrigation for the state's farmland and water supplies for cities and towns. Eighteen hot springs are still active in Colorado; the largest is at Pagosa Springs.