Riverton to Spearfish: Scenic Drive Guide

The drive from Riverton, Wyoming to Spearfish, South Dakota travels 310 miles, crossing the Continental Divide twice via US-26 and I-25. This route passes through the Wind River Canyon, where Precambrian granite walls rise 2,500 feet above the river, marking the southern limit of the Bighorn Mountains.

The most direct route is US-26 east to I-25 north, but the more scenic alternative follows US-16 through the Bighorn National Forest. Road conditions vary drastically: summer thunderstorms can trigger flash floods in the canyon, while winter brings closures on US-14A.

Natural Landscapes: Wind River Canyon, a 15-mile stretch between Riverton and Thermopolis, showcases layered shale and limestone before entering the Owl Creek Mountains. Further east, the Bighorn Basin’s badlands hide dinosaurs fossils, but the star attraction is Devil's Tower near Sundance, WY - the first US National Monument.

The route passes within 60 miles of the UNESCO-listed Yellowstone National Park trailhead, but the only official UNESCO World Heritage Site nearby is Yellowstone itself, best reached as a detour. Local commerce thrives in small towns like Tensleep, where an old - fashioned mercantile sells saddle leather goods and local honey.

For scenic turnoffs, pull into the Dry Fork Corral viewpoint off US-16 for panoramic sagebrush plains.

How long to drive Riverton, WY to Spearfish, SD is about 5 hours nonstop, but plan for 6-7 with breaks. Fuel stops are sparse between Riverton and Casper, so fill up before leaving. Wyoming has no state income tax but applies a 24-cent-per-gallon gas tax; prices typically run 20-30 cents less than in South Dakota.

Both Wyoming (80 mph) and South Dakota (80 mph) have speed limits on interstates, but US-26 is mostly 65 mph. The entire route is free of tolls. For smoother budgeting, consider diesel - many gas stations offer bulk discounts but lack easy RV parking.

• Fuel stop: Shoshoni, WY (32 miles east of Riverton) has an 8-pump Shell with restrooms.
• Casper, WY marks the halfway point, with 24-hour truck stops and fast food.
• Buffalo, WY offers the last fuel before the Big Horn Mountains.

Road quality is excellent on interstates, but US-16 through the Bighorn National Forest has steep grades and hairpin turns; use lower gears to avoid brake fade. Wildlife is common - watch for deer and elk especially at dusk.

Rest zones with picnic areas exist at Lost Cabin (mile 42) and Buffalo (mile 185). For families, the Thermpolis hot springs and the Spearfish Canyon's Bridal Veil Falls are easy toddler-friendly walks. Pets are welcome at most trailheads but must stay leashed; some motels in Buffalo charge extra for pets.

For planning stops, use how to find the best stops and hidden gems between cities to uncover local favorites.

Fatigue management: Switch drivers every 2 hours, and stop at the rest area near Clearmont, WY to stretch. Best stops Riverton, WY to Spearfish, SD include the historic Occidental Hotel in Buffalo, which has a genuine 1880s saloon.