Wyoming is one of the ROCKY MOUNTAIN states located in the west-central UNITED STATES. Rectangular in shape, it is bordered by MONTANA to the north, SOUTH DAKOTA and NEBRASKA to the east, COLORADO and UTAH to the south and IDAHO to the west.

With an area of 97,818 square mi (253,348 square km), Wyoming ranks 10th nationally in size. With the smallest population of any state (493,782), Wyoming remains a remarkably undeveloped state; cattle outnumber people by almost three to one. Because the western one-third of the state is covered by the Rocky Mountains, the state's average elevation is 6,700 ft (2,043 m), making it the second-highest in the continental United States behind Colorado. The lowest place in elevation is 3,099 ft (945 m) above sea level along the Belle Fourche River in the northeastern part of the state, while the highest point is Gannett Peak at 13,804 ft (4,207 m) in the Wind River Range.


There are four distinct geographic regions in the state: the Great Plains, the Southern Rocky Mountains, the Middle Rocky Mountains, and the Wyoming Basins. The Great Plains region is located mostly in the northeastern part of the state and consists of numerous low hills and isolated buttes. The most notable natural features of the region are the Thunder Basis Grasslands to the west of the Black Hills Region of South Dakota between Gillette, New Castle, and Sundance and the Devils Tower National Monument, a volcanic rock formation on the Belle Fourche River just north of Sundance in the far northeast corner of the state.

The Wyoming landscape becomes mountainous in the Southern Rocky Mountains south of the Great Plains where there are three main ranges: the Laramie Mountains, about 140 miles long; the Sierra Madre range, only about 30 mi (48 m) long; and the Medicine Bow Mountains, stretching over 50 mi (81 km) into the state from the Colorado border.

The Middle Rocky Mountains extend through the central, western, and northwestern parts of the state and contains the Wyoming Range, the Teton Range, the Absaroka Range, the Big Horn Mountains, and the Wind River Range. This phenomenal display of peaks, ridges, and deep valleys includes Gannett Peak in the Wind River Range, Wyoming's highest at 13,804 ft (4,208 m); Grand Teton in the Teton Range at 13,771 ft (4197 m); and Cloud Peak at 13,167 ft (4,014 m) in the Big Horns. The dramatic rise of the Grand Tetons in northwestern Wyoming, as seen from Jackson Hole, is thought to have formed as two separate blocks of the Earth's crust shifted, one block pushing the peak upward, while another hollowed out Jackson Hole below. North of the Tetons is Yellowstone, the first national park in the nation. This area is known for its unique geysers, extensive variety of plants and animals, and majestic views.

The largest geographic area is the Wyoming Basins. Situated among the state's various mountain ranges, the landscape spreads out into broad basins, which include the Bighorn Basin and Powder River Basin in the north, the Wind River Basin in the west-central region, and the Green River, Red Desert, and Washakie basins in the southwest. The rather flat and open eastern side of the state, except for the Black Hills region, drops gently into the Great Plains.

Crossing through the center of these basins is the Continental Divide. On the east side of the divide, waters flow into the MissouriMISSISSIPPI drainage system. On the opposite side, the Colorado and Columbia basins both have major contributors originating in Wyoming. More than 70 percent of the state's lakes, rivers, and streams eventually drain into the Missouri River finally reaching the ATLANTIC OCEAN. There is also a unique area in the Great Divide Basin where water flows neither eastward nor westward but remains trapped instead between one of the watersheds, forming a group of ponds known as Chain-of-Lakes.

The early development of Wyoming was closely linked with the fur trade and followed later by the great westward migrations. Although the French may have been in the area in the late 18th century, it was John Colter who brought fantastic stories to St. Louis in 1810 following several years of trapping in the Wyoming mountains. Some of the more famous of the early mountain men to explore the area include Thomas Fitzpatrick, James Bridger, Jedediah S. Smith, and Jeremiah Johnson. By the 1840s the route west through Wyoming was in steady use by settlers headed toward OREGON and CALIFORNIA and the old fur trading posts become stops along the Oregon Trail. In 1868 the region became the Territory of Wyoming, with Cheyenne as its capital. Although the fur trade entered a state of decline beginning in the 1840s, the territory continued to advance economically as huge herds of cattle were driven up from Texas along the cattle trails. Population growth and economic development continued in the late 1800s. Wyoming joined the Union in July 1890. In 1924, Wyoming became the first state to elect a woman governor, Nellie Tayloe Ross.

Most of the state's residents are either directly or indirectly involved in farming or ranching. The major dry-farming products include hay, wheat, and barley, and where irrigation is used to supplement the arid conditions, sugar beets and dry beans can be produced. Because much of the land is high desert with little precipitation and sparse grass cover, livestock operations necessitate large grazing areas for each animal. Sheep graze in places unfit for cattle, and both sheep and cattle are allowed to range by permit in the national forests. In 2000, Wyoming ranked second among the states in wool production and third in sheep and lambs.

Mining is the largest sector of the state's economy, accounting for about one quarter of the gross state product. Petroleum is the state's most important mineral; the production of petroleum and petroleum products is centered in Casper. Natural gas is also of considerable economic significance, as well as coal, sodium carbonate, and uranium. Wyoming has the world's largest sodium carbonate deposits and has the nation's second largest uranium deposits. Considerable amounts of gold, iron, and various clays are also mined. Important manufactures include processed foods and clay, glass, and wood products.