Salmon to Island Park: Idaho's Scenic Highway 28

Highway 28 between Salmon, ID and Island Park, ID is a 79-mile ribbon of asphalt that climbs over 5,000 feet in elevation change, passing through the Bitterroot and Centennial mountain ranges. This route is the only direct link between the Lemhi Valley and the Island Park Caldera, one of Earth's largest volcanic features. Unlike the interstate-dominated corridors of southern Idaho, this drive offers a raw, unfiltered look at the state's wild heart.

The road itself is a lesson in geology: you'll start in sagebrush-covered valleys at 4,000 feet, then ascend through Douglas fir forests before topping out at 7,072-foot Gilmore Summit. The pavement is generally good, but winter weather can close the pass unexpectedly. For a detailed look at how to plan for hidden gems along such routes, see how to find the best stops and hidden gems between cities.

The landscape shifts from stark sagebrush to lush forest as you climb. The Lemhi River follows you for the first 20 miles, a blue-green ribbon popular with fly fishers. Near the town of Leadore (population 10), you'll spot historic ranches and the remnants of gold mining operations from the 1870s. Farther along, the Continental Divide trail crosses under the highway at Gilmore Summit, offering a rugged hike for adventurous souls.

Local commerce is sparse but authentic. In Leadore, the Leadore Inn serves up basic American fare and opens at 7 AM for early travelers. A few miles south, the Tendoy General Store (open until 8 PM) stocks groceries, ammo, and fishing gear. Dairy farms in the Lemhi Valley produce raw milk, available at a roadside stand near mile 12 (honor system). For a taste of local culture, stop at the Sacajawea Interpretive Center in Salmon to learn about the Lemhi Shoshone tribe.

This road is safe in summer, but winter brings ice and snow from October to May. Carry chains if traveling off-season. For families, the route offers easy pull-offs for picnic with minimal hazards. The Island Park area has several developed campgrounds like Ponds Lodge (approx. $30/night) with restrooms and water. For children, the Mesa Falls Scenic Byway (a short detour at the south end) is a must-see with its 114-foot waterfall.

Family and Pet Friendly Points

• Pet-friendly: Many pull-offs allow leashed pets; the Salmon-Challis forest has no leash restrictions in undeveloped areas.
• Rest stops: Formal rest areas exist at mile 35 (near Gilmore) and mile 58 (near the intersection with Forest Road 215).
• Fatigue: The long straight stretches can induce drowsiness; plan to stop at the Leadore or Island Park junctions.

Hidden off-route spots include the Copper Basin Loop (turn at mile 30, dirt road, 20-mile detour) with its alpine lakes, and the remains of the Gilmore Ghost Town, visible from the summit. For safety, watch for elk and moose, especially at dusk near water crossings. If driving at night, expect no street lights; use high beams when clear.

Driving time from Salmon to Island Park is typically 1 hour 40 minutes without stops, but plan on 3 hours if you explore. There are no gas stations between mile markers 20 and 60, so fill up in Salmon (last stations) or at the junction with US-20 near Island Park. As of 2024, fuel prices in Salmon average $3.50/gallon, while Island Park stations run about $0.20 higher due to remoteness. The route passes through Salmon-Challis National Forest and Targhee-Caribou National Forest, both offering free backcountry camping with a valid pass.

Key Road Facts

• Road condition: Paved two-lane, mostly 55 mph, with occasional sharp curves and wildlife crossings.
• Elevation: Gilmore Summit (7,072 ft) is the highest point; no services at the summit.
• Cell coverage: Sprint and T-Mobile drop out near Leadore; AT&T covers most of the route.