Discovery of gold near South Pass in the 1860s led to the creation and settlement of short-lived South Pass City, Wyo. and other settlements nearby. The Carissa Mine was one of the richest, but between 1867 and 1869, 1500 lodes were located during the rush, and as many as 2,000 miners and others may have lived in the little town or on their claims. By the early 1870s, only a few hundred were left. Sporadic gold production has continued since, however, with systematic prospecting by an American subsidiary of a Canadian firm permitted as recently as 2006.

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.

In the 1820s and 1830s, what’s now western Wyoming was at the center of the fur trade of the northern Rocky Mountains. Indians, trappers and their suppliers met each summer at a big trade fair called rendezvous, where trappers exchanged their season’s beaver pelts for hardware, whiskey and supplies. By 1840, demand for beaver had disappeared and the species had been nearly rubbed out. But the rendezvous supply routes were already becoming the trails that would bind the nation together.

The Piedmont Charcoal Kilns southwest of Evanston, Wyo. were built in 1869 to supply charcoal primarily to Utah mining and smelting operations. The town of Piedmont’s location—on the Union Pacific Railroad but near a ready timber supply in the Uinta Mountains—made it a logical spot for the industry. Most of the charcoal was shipped to the Salt Lake valley, and some to Fort Bridger for use in blacksmith forges and heating stoves. Piedmont was a railroad station on the Union Pacific line. Three of the original five kilns remain standing. The site is on the National Register of Historic Places.

The JC Penney Company, long among the world’s largest department store chains, traces its roots to a one-room shop in a small Wyoming coal-mining town at the turn of the last century. Penney’s career in Wyoming lasted just a decade, but in 1902, Wyoming provided exactly what young Penney needed to found a chain that has survived, as of 2011, for 109 years.