Thermopolis to Rock Springs: A Road Trip Guide

The drive from Thermopolis to Rock Springs follows US-20/US-26 southwest, crossing the Wind River Canyon and traversing the high desert of central Wyoming. The route covers roughly 120 miles, typically taking 2 hours and 30 minutes without stops.

Thermopolis is home to the world's largest mineral hot spring, with water flowing at 127°F from the Big Horn Spring. The town's Hot Springs State Park offers free public bathing in the state bath house, a tradition rooted in an 1896 treaty with the Arapaho and Shoshone tribes.

The highway is mostly straight, but watch for wildlife, especially deer and antelope at dawn and dusk. Winter conditions can be icy, and snowplows operate frequently; always carry chains in winter.

For families, the Hot Springs State Park in Thermopolis offers a splash park, a swinging bridge, and a buffalo herd, making it a top stop. Between Thermopolis and Rock Springs, other family-friendly options include the Wind River Canyon Picnic Area, which has tables and short trails, and the Riverton City Park with playgrounds and shade.

Pets are welcome at many roadside stops, but be cautious with heat and wildlife. The state park has designated pet-friendly trails, and Shoshoni's rest area has a small dog run.

To combat fatigue, take a break at the Shoshoni Rest Area (milepost 55) or the Sweetwater Rest Area (milepost 76). Both have picnic tables and vending machines. Also, the Wind River Hotel and Casino in Riverton offers a safe place to stretch your legs, though gambling is not allowed for minors.

Essentially, this route is a two-hour drive with minimal distractions, so plan ahead for stops. For a quick refuel, the Sinclair station in Shoshoni is reliable, and the Maverik in Riverton is open 24/7.

US-20/US-26 is a well-maintained two-lane highway, with occasional passing lanes on grades. The route passes through Shoshoni, a small town at the confluence of the Wind and Bighorn rivers, and continues southwest toward Riverton before joining US-287 South. Past Riverton, the road becomes US-287/US-26, with a four-lane divided section near Rock Springs.

• Fuel: Plentiful in Thermopolis, Shoshoni, Riverton, and Rock Springs. Plan to fill up before leaving Thermopolis; the gap between Riverton and Rock Springs is about 60 miles with no services.
• Food: Diner options in Shoshoni (e.g., the Shoshoni Diner) and Riverton (multiple fast-food and sit-down restaurants).
• Restrooms: Available at gas stations, rest areas near Shoshoni and Jeffrey City (but Jeffrey City is now almost a ghost town).

For insights on finding unexpected gems along this route, see how to find the best stops and hidden gems between cities.

The Wind River Canyon, just south of Thermopolis, is a dramatic 2,500-foot-deep gorge with walls of granite and limestone, carved by the Wind River. This segment is geologically significant for its Precambrian rock formations, some over 2.7 billion years old.

Beyond the canyon, the landscape opens into the Wind River Basin, where sagebrush steppe stretches to the horizon. This semiarid region receives only 8-12 inches of annual precipitation, making it one of Wyoming's drier areas. Summer temperatures often exceed 90°F, while winters bring bitter cold and occasional snow.

Local commerce in Thermopolis revolves around tourism, with mineral springs and dinosaur digs nearby. Further south, Riverton serves as a regional hub for agriculture and ranching, hosting the annual Fremont County Fair in August. In Rock Springs, the history of coal mining is preserved at the Western Wyoming Community College's Natural History Museum.

A notable detour: The Dubois Badlands, about 30 miles northwest, offer scenic badlands formations. For a unique geological stop, consider the Hudson Fossil Ridge, where you can view dinosaur tracks without admission.