The scenic Bighorn Basin and world-class fishing opportunities on the Bighorn River have made Big Horn County, Wyo., a tourist destination, but the area is also rich in oil and natural gas—and history. People have lived in the area since ancient times, as evidenced by the Medicine Wheel near the county’s northern corer. Ranch families still raise cattle and sheep, and farm families still raise sugar beets as they have for more than a century.

Home to 19 of Wyoming’s first families, the Historic Governor’s Mansion was occupied from 1904 through 1976, opened to the public in 1977 and extensively renovated in 2004.

Though the site was an important river crossing on the early frontier, the town of Casper did not begin until 1888, when the Fremont, Elkhorn & Missouri Valley Railroad reached the area. The town immediately became an important shipping point for cattle and wool. The first oil refinery was built in 1895 to process crude oil from the Salt Creek Oil Field, 40 miles to the north. The first true oil boom began after 1910 and lasted through the mid 1920s, and the town’s fortunes have been closely connected to the energy business ever since. In 2010 the city’s population passed 55,000. Casper continues as a retail, medical and energy-industry service hub.

Washakie County, formed in 1911 and named for the Shoshone Chief Washakie, continues to rely upon energy and agriculture as its main industries.

W. Edwards Deming grew up in difficult financial circumstances in Powell, Wyo., early in the 20th century. Still, he worked his way through the University of Wyoming and Yale and became absorbed by statistics as a way to solve problems. After World War II, he shared his ideas on efficiency with Japanese manufacturers eager to rebuild their shattered economy. The Japanese used that knowledge to flip the global economy on its head and beat U.S. industry at its own game.

Verda James, a schoolteacher, deputy director of public instruction for the state of Wyoming, assistant superintendent of the Natrona County schools, and later a faculty member at Casper College, was first elected to the Wyoming House in 1954. She served eight terms. During the last term, 1969-1970, she was elected House speaker, the first woman to serve in that position for a full term.

Upton, Wyo., known originally as Irontown or Iron City, and later as Merino, began in 1890 as a Burlington Railroad depot near a set of sheep corrals. The town was not incorporated until 1909. The Burlington’s successor, the BNSF, remains an important employer today, as do the school district and a clinic operated by Weston County Health Services.

Uinta County, one of the five counties of Wyoming Territory, was reduced to its present size in 1911. The Oregon, California, Mormon and Overland trails all passed through the county as well as the Union Pacific Railroad, the Lincoln Highway and Interstate 80. While the county is rich in natural resources like coal and oil and endures economic booms and busts as a result, agriculture continues to be a mainstay. Rancher John Myers established the first ranch on the Bear River drainage in 1858 and filed the first water right in what later became Wyoming Territory.

As many as half a million people crossed what’s now Wyoming in the mid-19th century before the transcontinental railroad was built. Their trails followed the North Platte and Sweetwater rivers west to South Pass, after which they divided into various routes bound for Oregon, Utah or California. They were making the journey of a lifetime, on routes blazed by Indians and trappers, and then worn deep and wide by thousands of wagons and perhaps millions of draft animals. These trails remain largely unchanged in Wyoming. Their white-topped wagons still hold an important place in the national imagination.

Trail End, the mansion home of cattleman, banker and politician John B. Kendrick, was completed on a hilltop overlooking Sheridan, Wyo. in 1913, 16 months before Kendrick was elected governor. Kendrick later served three terms in the U.S. Senate and died in 1933. The Kendrick family continued to use the house until 1961. In 1968, the Sheridan County Historical Society bought the building, and in 1982 transferred ownership to the state, which operates the 14,000-square-foot mansion now as a state historic site.