McCall to Thermopolis: A Road Trip Through Wild Beauty

The road from McCall, Idaho to Thermopolis, Wyoming follows the ancient path of the Payette and Snake Rivers, crossing the Continental Divide at an elevation of 7,037 feet via Teton Pass (US 20). This 540-mile journey traverses three states—Idaho, Montana, and Wyoming—and traces the route of the Oregon Trail pioneers who forded the North Platte River near present-day Thermopolis. The drive typically takes 8.5 hours without stops, but the landscape demands lingering: from the granite peaks of the Sawtooth Range to the ochre badlands of the Bighorn Basin. Notably, the stretch between Idaho Falls and West Yellowstone is prone to sudden snow squalls even in summer, a quirk of the high desert climate. For guidance on discovering unexpected treasures en route, refer to how to find the best stops and hidden gems between cities.

The most efficient path from McCall to Thermopolis is via US-95 South to I-84 East, then I-15 North to US-20 East through Idaho Falls and over Teton Pass. At West Yellowstone, turn onto US-191 South through Montana's Gallatin Canyon, then follow US-287 East to Thermopolis. Key logistics include:

• Fuel: Fill up in McCall (last cheap gas until Cascade); Idaho Falls and West Yellowstone are reliable midpoints. Avoid fuel stops in the Bighorn Basin after 9 PM—stations close early.
• Tolls: None, but Teton Pass (WY-22) is a seasonal alternate if US-20 is closed; it adds 30 minutes and has a scenic overlook at 8,431 ft.
• Road Conditions: US-20 over the Continental Divide is plowed year-round, but snow tires required November–March. The stretch between Dubois and Thermopolis on US-26 has narrow shoulders and wildlife crossings.

Accommodation clusters: McCall has lakeside lodges; Idaho Falls offers budget chains; West Yellowstone is a gateway to Yellowstone National Park with premium summer rates; Thermopolis has motels and the historic Hot Springs State Park lodge. Book ahead in July–August. For those wondering how long to drive McCall, ID to Thermopolis, WY, the nonstop time is 8.5 hours, but plan for 10–12 with scenic breaks.

Infrastructure safety is generally high, but long stretches have no cell service (especially between Monida, MT and Dubois, WY — about 80 miles). Carry paper maps and a satellite messenger. Wildlife collisions are a real risk; deer and elk are active at dusk, particularly near Big Hole National Battlefield (MT) and Wind River Canyon. Speed limits are 70 mph on interstates, 55–65 on two-lane highways; Wyoming has a consistent 70 mph on US-26. For child suitability, stop at the Idaho Falls Zoo or the Grizzly & Wolf Discovery Center in West Yellowstone. Pet-friendly framework includes the Harriman State Park trail near Island Park, which allows dogs on leash, and the Hot Springs State Park's picnic area with dog water stations.

Fatigue management rest zones: McCall (city park), Idaho Falls (at the Snake River Greenbelt, mile marker 0 on I-15), and Thermopolis (the State Park's plaza). For hidden off-route spots, take the gravel road to the Sawtell Peak Observatory (9 miles south of West Yellowstone) for a 360-degree view of the Tetons. Another gem is the ghost town of Kirwin, Wyoming — a 20-mile unpaved detour from US-26 near Meeteetse, featuring abandoned gold mine structures. Things to do between McCall, ID and Thermopolis, WY include rafting the Payette River near Banks (Class III–IV rapids) and soak in the free hot springs at the Star Plunge in Thermopolis.

The route unfurls through three distinct ecoregions: Idaho's Payette River Canyon with its basalt cliffs and ponderosa pines; Montana's Madison River valley flanked by the Madison Range; and Wyoming's Wind River Corridor, where red desert gives way to the Owl Creek Mountains. Geological marvels include the Mesa Falls (scenic detour: take ID-47 to Upper Mesa Falls, a 114-foot cascade) and the Grand Teton view from US-26 east of Jackson. UNESCO World Heritage Sites nearby: Yellowstone National Park (45 minutes from West Yellowstone) and the nearby fossil dig at the Florissant Fossil Beds in Colorado (a 5-hour detour, not on route).

Local commerce thrives in agricultural towns: in St. Anthony, Idaho, stop at the Willard Produce Stand for huckleberry jam and raw honey. In West Yellowstone, the historic Playmill Theatre offers live performances from June to September. Thermopolis's Hot Springs State Park is free to enter, and the Wyoming Dinosaur Center has a full-scale Diplodocus skeleton. The best stops McCall, ID to Thermopolis, WY include the Teton Valley Historical Museum in Driggs, Idaho, and the Red Barn Gift Shop in Dubois, Wyoming, known for custom leather goods. Many travelers ask is it worth driving McCall, ID to Thermopolis, WY — unequivocally yes for the solitude and geothermal wonders.