6 core states · up to 8 · 14,663,034 people (core) · Mountain time
Rocky Mountain states map
The Rocky Mountain states are the six the range actually crosses — Montana, Idaho, Wyoming, Colorado, Utah and New Mexico. Nevada and Arizona are often added to make the group match the Census Mountain division.
How the region is defined
"Rocky Mountain states" can mean two things. Strictly, it is the states the Rocky Mountains run through: Montana, Idaho, Wyoming, Colorado, Utah and New Mexico — six states whose high points are all Rocky Mountain summits. Loosely, it is a synonym for the Census Mountain division, which adds Nevada and Arizona, neither of which has any part of the Rockies (their mountains belong to the Basin and Range). This site's table lists both groups and marks which is which.
The six core states had 14,663,034 people in 2020 on 639,003 square miles; with Nevada and Arizona the totals are 24,919,150 people on 863,565 square miles. Colorado has about 39% of the core population. Denver (715,522), Albuquerque and Salt Lake City are the only core-state cities above 200,000.
States, capitals and largest cities
| State | Capital | Largest city | Population (2020) | Area (sq mi) | Included |
|---|---|---|---|---|---|
| Colorado (CO) | Denver | Denver | 5,773,714 | 104,094 | Always |
| Wyoming (WY) | Cheyenne | Cheyenne | 576,851 | 97,813 | Always |
| Montana (MT) | Helena | Billings | 1,084,225 | 147,040 | Always |
| Idaho (ID) | Boise | Boise | 1,839,106 | 83,569 | Always |
| Utah (UT) | Salt Lake City | Salt Lake City | 3,271,616 | 84,897 | Always |
| New Mexico (NM) | Santa Fe | Albuquerque | 2,117,522 | 121,590 | Always |
| Nevada (NV) | Carson City | Las Vegas | 3,104,614 | 110,572 | Sometimes |
| Arizona (AZ) | Phoenix | Phoenix | 7,151,502 | 113,990 | Sometimes |
| Total, all listed (8 states) | 24,919,150 | 863,565 |
Geography
The Rockies enter the United States in Montana's Glacier National Park and run about 1,500 miles to the Sangre de Cristo range near Santa Fe. They are not one range but dozens: the Bitterroots on the Montana–Idaho line, the Absarokas and Wind Rivers of Wyoming, the Tetons, the Uintas of Utah (the only major range running east–west), and Colorado's Front Range, Sawatch, San Juans and Elk Mountains. Colorado has 53 peaks above 14,000 ft, led by Mount Elbert (14,440 ft), the highest in the Rockies. Wyoming's Gannett Peak (13,804 ft), Utah's Kings Peak (13,528 ft), New Mexico's Wheeler Peak (13,161 ft), Idaho's Borah Peak (12,662 ft) and Montana's Granite Peak (12,807 ft) are the other high points.
The Continental Divide follows the crest through all six core states except Utah (it passes east of the state through Wyoming and Colorado). Rivers rising in the Rockies reach three oceans: the Missouri, Platte, Arkansas and Rio Grande to the Atlantic via the Gulf; the Colorado and Snake to the Pacific; and the Saskatchewan headwaters in Glacier to Hudson Bay. Yellowstone, Grand Teton, Glacier and Rocky Mountain national parks are all in the core states.
Between the ranges are high basins — South Park, the Wyoming Basin, the San Luis Valley — and east of them the mountains drop abruptly to the Great Plains along a front that Denver, Colorado Springs, Cheyenne, Billings and Great Falls all sit against. All six core states are on Mountain time except the Idaho panhandle.
Related maps
- Official version: Mountain division and the West region.
- Overlapping informal regions: Southwest, Great Plains, Pacific Northwest.
- Quiz: Western states quiz.
- Cities: Denver, Colorado Springs, Albuquerque, Salt Lake City, Boise; capitals Helena, Cheyenne, Santa Fe.
- Geography: Rocky Mountains, Continental Divide, Yellowstone, State high points.