10 states · Canada to Texas · roughly the 100th meridian to the Rockies · about 500 miles wide
Great Plains map
The Great Plains are the high, dry grassland between the Rocky Mountains and the 100th meridian, stretching from the Canadian border to Texas across ten states.
Where the Great Plains are
The Great Plains lie east of the Rockies and west of the humid Midwest. The western edge is sharp: the foothills of the Front Range. The eastern edge is a matter of rainfall, usually put near the 100th meridian, where annual precipitation drops below about 20 inches and trees give way to short grass. The plains slope gently east, from about 5,000–6,000 ft at the base of the Rockies to about 1,500 ft along the eastern edge, so what looks flat is actually a long ramp.
States on the plains
- Montana — the eastern two-thirds of the state.
- North Dakota and South Dakota — everything west of the Missouri, including the Badlands and the Black Hills.
- Wyoming — the eastern third, including Cheyenne.
- Nebraska — the Sandhills and the Panhandle; the eastern quarter is Corn Belt.
- Colorado — the eastern third, east of the Interstate 25 corridor.
- Kansas — the western two-thirds, including the Flint Hills tallgrass on the eastern edge.
- Oklahoma — the Panhandle and western half.
- New Mexico — the eastern strip, Clovis to Hobbs.
- Texas — the Panhandle and the Llano Estacado around Lubbock and Amarillo.
The Census Bureau's Great Plains region page lists which states are usually grouped under the name.
Key features
- Black Hills, South Dakota — an island of granite mountains; Black Elk Peak, 7,242 ft, is the highest point in the US east of the Rockies. Mount Rushmore is here.
- Badlands — eroded clay in South Dakota (a national park) and North Dakota (Theodore Roosevelt National Park).
- Nebraska Sandhills — about 19,000 square miles of grass-covered dunes, the largest dune field in the western hemisphere.
- Llano Estacado — a flat cap-rock plateau in Texas and New Mexico, edged by cliffs.
- Ogallala Aquifer — the groundwater under eight plains states that irrigates the wheat, corn and cotton; it is being pumped faster than it refills.
- Rivers: the Missouri, Yellowstone, Platte, Republican, Arkansas, Cimarron, Canadian and Red all cross the plains from west to east.
Cities
The plains have few large cities. Denver and Colorado Springs sit on the western edge; Oklahoma City, Wichita, Omaha and Lincoln sit on the eastern edge. Inside are Billings, Bismarck, Rapid City, Cheyenne, Amarillo and Lubbock. Long stretches of the northern plains have fewer than two people per square mile.
How the plains shaped the map
With no rivers or ridges to follow, the plains states were drawn with rulers: the Dakotas, Wyoming, Colorado, Kansas and the Oklahoma and Texas Panhandles are all bounded by parallels and meridians. The Homestead Act of 1862 divided the land into 160-acre squares, which is why roads and fields form a grid visible from the air. The 1930s Dust Bowl, centred on the Oklahoma and Texas Panhandles and southwest Kansas, followed ploughing of the short-grass prairie.
Related maps
- Great Plains states — the region page with populations and capitals.
- Rocky Mountains · Missouri River · US mountain ranges.
- Central Time Zone — the Mountain/Central line crosses the plains in Nebraska, Kansas, the Dakotas and Texas.
- All geography maps.