Idaho Falls to Wallace: Ultimate Road Trip Guide

This 500-mile route along I-15 and I-84 traces the Snake River Plain, climbs into the Salmon River Mountains, and ends in the historic Silver Valley. You will pass through six distinct climate zones.

The drive typically takes 7.5 to 8.5 hours without extended stops. The elevation gain from Idaho Falls (4,700 ft) to Wallace (2,700 ft) is deceptive — multiple passes exceed 7,000 ft.

Learn more about how to find the best stops and hidden gems between cities.

Local quirk: The US-93 between Challis and Salmon is known as the "Sawtooth Scenic Byway" — despite the name, it actually skirts the Pahsimeroi Valley, not the Sawtooths.

The Snake River Plain near Idaho Falls offers stark lava fields and Craters of the Moon National Monument (detour 20 mi). As you climb north, the terrain transitions to pine forests and river canyons.

• Craters of the Moon: Volcanic basalt flows, cinder cones, caves (entry $20/vehicle)
• Birthplace of the Atomic Age: Arco was the first town powered by nuclear energy in 1955 (sign on US-20)
• Sawtooth Scenic Byway (US-93): Scenic drive along the Salmon River, with pullouts for wildlife viewing (elk, bighorn sheep)
• Sacajawea Interpretive Center (Salmon): Free museum about the Lemhi Shoshone and Lewis and Clark

Wallace is a National Historic Landmark District with intact 19th-century buildings. The Oasis Bordello Museum (adults only) and the Wallace Mining Museum reflect the town's silver-mining past.

Local commerce leans toward outdoor gear, antique shops, and small cafes. The Blackboard Cafe and The Fainting Goat are popular lunch stops.

UNESCO World Heritage Sites: None directly on route, but the nearby Yellowstone National Park (south of Idaho Falls) is a UNESCO site. A detour adds 2 hours each way.

Road quality on I-15 and I-84 is excellent. US-93 is well-maintained but narrow in sections; watch for logging trucks between Salmon and Missoula. Winter conditions can bring ice and snow from November through April.

• Cell coverage: Strong on interstates, spotty on US-93 between Challis and Salmon
• Emergency services: Limited in remote areas; dial *ID (state police) or 911
• Rest stops: Official rest areas near Arco (MM 159), Lost Trail Pass (MM 340), and Lookout Pass (MM 5)

Family and child suitability: High — multiple educational stops (atomic history, Lewis & Clark, mining). Kids enjoy Craters of the Moon's caves and the walking paths in Wallace. Many parks along the route have playgrounds.

Pet-friendly framework: Most national forest lands allow leashed pets. Hotels in Challis, Salmon, and Wallace generally accept pets (fees ~$25/night). Rest stops have designated pet relief areas.

Fatigue management: Plan breaks every 2 hours. Recommended rest stops include Arco's lava flow picnic area, the Salmon River viewpoint near North Fork (restroom and short trail), and the lookout at Lookout Pass (historic ski area).

Hidden off-route spots: The hot springs in the Challis area (e.g., Gold Bug Hot Springs near Salmon, 2-mile hike) and the ghost town of Burke (abandoned mining camp just north of Wallace).

The backbone of the trip is I-15 south to I-84 west near Pocatello, then US-93 north through the vast Challis National Forest. After Salmon, ID, the route crosses into Montana at Lost Trail Pass (7,040 ft) and rejoins I-90 west to Wallace.

Fuel stations are sparse between Arco and Missoula — plan to fill up in Arco, Challis, Salmon, and Missoula. Gas prices tend to be $0.20-$0.40/gallon higher in remote towns.

• Total distance: 499 miles
• Driving time without stops: 8 hours
• Recommended fuel stops: Arco, Challis, Salmon, Missoula
• Road conditions: Check 511.idaho.gov for US-93 closure info (frequent in winter)

The route includes three notable mountain passes: Monida Pass (6,869 ft), Lost Trail Pass, and Lookout Pass (4,725 ft) just before Wallace. Watch for steep grades and runaway truck ramps.