Thermopolis to Pierre: Scenic Drive & Hidden Gems

This 330-mile drive along US-20/US-16 and I-90 crosses the Bighorn Basin and the Black Hills, with the Missouri River at its end. The Continental Divide splits water flow at about mile 160, just east of Buffalo. The route climbs to 6,500 feet at Powder River Pass, then descends to 1,400 feet in Pierre.

The fastest route is US-20 east to Buffalo, then I-90 east to exit 185 at Sundance, then US-14/85 south to US-14 east to Pierre. Driving time is 6 hours, with an extra 30 minutes for construction delays. Fuel is $3.50/gal in Wyoming and $3.20 in South Dakota, so fill up in Sundance's Love's truck stop at exit 185. The route has full cell coverage except a 30-mile dead zone between Buffalo and Gillette. Gas station density is one per 20 miles in Wyoming and one per 30 miles in South Dakota.

• Estimated drive time: 6 hours, 330 miles.
• Major roads: US-20, I-90, US-14/85, US-14.
• Cost: $45 in fuel for a standard sedan.

Most roads are two-lane with frequent wildlife crossings; dawn and dusk are peak deer activity, especially near Keyhole Reservoir. Road quality is good: I-90 is recently repaved, while US-20 has some potholes east of Buffalo. Cell coverage gaps mean download offline maps. Services are limited on Sundays; some small towns close gas stations by 8 PM. Winter storms can close passes, but the route is typically open year-round.

For families, the Wind River Wild Horse Sanctuary near Thermopolis offers 30-minute tours ($10 per car), and the Mammoth Site in Hot Springs (SD) is a 45-minute detour with many fossils. Pet-friendly stops include the Powder River Pass rest area, which has a designated dog run, and the Lewis and Clark Lake Recreation Area in Pierre offers a fenced dog park. This stop also has playgrounds and frisbee golf.

Fatigue management: Rest areas every 50 miles, with the best at mile 220 (near Moorcroft) and mile 280 (near Fort Pierre). The 24/7 Love's truck stop in Sundance has a restaurant, showers, and a quiet room. For a power nap, pull into the rest area at mile 190 with ample shade. Drive during daylight to spot wildlife; night driving is discouraged.

Local commerce includes the Sturgis Motorcycle Museum, open year-round, and the Old Courthouse in Deadwood, six miles off I-90. The Devil's Tower KOA offers teepee rentals, and the Buffalo Chamber of Commerce provides maps for self-guided historical walking tours.

The route showcases the sheer cliffs of the Bighorn Basin, the pine-dotted slopes of the Bighorn National Forest, and the rolling prairies of the Great Plains. The Black Hills rise abruptly near Sundance, home to 7,000-foot peaks and the famous Devil's Tower, a 1,267-foot monolith that's a UNESCO World Heritage Site. The route passes through three state parks: Buffalo Bill State Park (WY), Keyhole State Park (WY), and Farm Island State Recreation Area (SD).

Local culinary options include Thermopolis's hot springs-fed cafe, Buffalo's historic Occidental Hotel, and Sundance's famous hamburger stand. In Pierre, try the pheasant sandwich at the Cattleman's Club. For culture, the Wyoming Dinosaur Center in Thermopolis and the Pierce Museum in Buffalo offer local history. For how to find the best stops and hidden gems between cities, see the linked guide.

Hidden off-route spots include the ten-mile stretch of the Bozeman Trail, marked by wagon ruts near Big Piney, and the silent city of Spotted Horse, a ghost town with a preserved saloon. For shopping, the Sundance Mercantile sells authentic Western gear, and Pierre's Farmers Market offers local honey and chokecherry jam from August to October.