Salmon ID to Kemmerer WY: Road Trip Guide

This route crosses part of the Idaho-Montana-Wyoming border region, a corridor where the Continental Divide and the Oregon Trail intersect. The drive covers approximately 450 miles (724 km) and takes roughly 8–9 hours of pure driving time, excluding stops. Notable: Salmon, ID, sits at the confluence of the Salmon and Lemhi Rivers, while Kemmerer, WY, is home to the first J.C. Penney store. One key driving quirk: the route climbs over Teton Pass (elevation 8,431 ft) in Wyoming, which can close briefly in winter due to avalanches; check road conditions before departure.

Fuel tends to become scarcer between Idaho Falls and Kemmerer, with stretches of over 100 miles without services. The average gas price along the route may be about 5–10% higher than national averages, especially in remote areas. In 2024, the federal mileage reimbursement rate is $0.67 per mile, so driving this route costs roughly $300 in vehicle expenses alone, not food or lodging.

The primary highways are US-93 south from Salmon to Mackay, then ID-33 over to Idaho Falls, then US-26 east through Swan Valley and into Wyoming, joining US-89 and US-30 to Kemmerer. Alternatively, take I-15 from Idaho Falls to US-30 at Pocatello, cutting off about 30 minutes but bypassing the scenic Teton views. For the most scenic route, stick to US-26 and US-89, which follows the Snake River and offers views of the Tetons from the east.

• Cell service is intermittent; download offline maps in advance.
• Fuel up in Salmon, Idaho Falls, and Kemmerer—the largest towns.
• Cellular coverage becomes spotty near the Wyoming border.

Road quality: US-93 and US-26 are well-maintained, but winter conditions can affect traction. In summer, construction delays possible. All roads are paved and suitable for standard vehicles. For EV drivers, charging stations exist in Idaho Falls and Kemmerer, but sparse elsewhere—plan to charge overnight.

• No tolls on this route.
• Ferry? No—crossings of the Snake River are by bridge.

The drive passes through the Lemhi Valley, the Lost River Range, and the Snake River Plain, then ascends into the Caribou-Targhee National Forest. Notable landmarks include the Teton Range from the east side, and the fossil-rich limestones of Kemmerer—home to the famous Fossil Butte National Monument. This monument is a UNESCO World Heritage preliminary site (on the tentative list), preserving an ancient lakebed ecosystem from 50 million years ago.

Local commerce along the way: small towns like Mackay (population ~500) and Alpine, WY offer basic diners and convenience stores. In Kemmerer, try the historic J.C. Penney Museum, which details the founding of the retail chain in 1902. For a taste of local culture, visit the Salmon Valley Farmer's Market (summer Saturdays) or the Fossil Country Frontier Days in Kemmerer (late July).

• Natural attractions: Harriman State Park (Idaho) – 16 miles of trails through wildlife refuges.
• Teton Scenic Byway (WY-33) – a detour worth considering if time permits.
• Kemmerer's Fossil Butte – over 30,000 fish fossils excavated.

In winter, carry chains and emergency supplies; Teton Pass and Pine Creek Pass (elevation 7,000 ft) can be icy. In summer, watch for wildlife, especially deer and elk at dawn/dusk. The route includes long stretches with no services—plan rest stops every 2 hours to prevent fatigue. Recommended rest areas: the Lost River Rest Area (mile 56 on US-93) and the Alpine Rest Area on US-89.

For families, the Idaho Falls Zoo (named one of top zoos in the U.S. for kids) makes a great halfway stop. The drive offers plenty of leg-stretching spots: the Colter Bay Visitor Center in Grand Teton NP is a bit off-route but worth the 30-minute detour. For pets, most rest areas and national parks are pet-friendly, but keep them leashed; some trailheads may not allow dogs. In alpine zones, temperatures can swing 40°F in a day, so pack layers.

• Best family stop: Idaho Falls Zoo (843 S 15th E, Idaho Falls, ID 83402).
• Pet etiquette: clean up and carry water.
• Fatigue: consider an overnight in Idaho Falls.

For more on optimizing your journey, check out this guide on how to find the best stops and hidden gems between cities.