Salmon to Anacortes: Epic Idaho-Washington Road Trip Guide

The route from Salmon, ID to Anacortes, WA covers roughly 750 miles and crosses the Continental Divide at Lost Trail Pass (elev. 7014 ft) within the first hour. This drive transitions from the sagebrush steppe of the Salmon River Valley to the temperate rainforests of the Pacific Northwest, offering dramatic geological and ecological shifts.

Total driving time is about 12.5 hours without stops, but expect 2-3 days to fully appreciate the journey. The route primarily follows US-93 north to Missoula, MT, then I-90 west through the Idaho Panhandle and Washington, ending on WA-20 to the ferry terminal in Anacortes.

The climate transitions from semi-arid with hot summers (Salmon averages 90°F in July) to maritime mildness in Anacortes (highs around 70°F). Rainfall increases dramatically west of the Cascades, supporting dense evergreen forests and agricultural valleys.

The route passes near no UNESCO World Heritage Sites; the nearest is Glacier National Park (Montana), a 2-hour detour from Missoula. However, the Craters of the Moon National Monument (Idaho) is a unique volcanic landscape, though off-route.

Local commerce thrives in small towns: pick up huckleberry products in Wallace, ID; visit the historic Davenport Hotel in Spokane; and sample farm-to-table cuisine in Ellensburg, WA. The Skagit Valley near Anacortes is renowned for its tulip fields and seasonal festivals.

Fuel stops are spaced 60-80 miles apart, so plan accordingly. Gas prices in Idaho are typically 10-15 cents cheaper per gallon than in Washington. The route is well-served by interstate-quality highways, with some two-lane sections on US-93 in Montana.

For optimizing stops, consult how to find the best stops and hidden gems between cities. The journey includes several scenic byways: the Salmon River Scenic Byway (ID-28) and the International Selkirk Loop in northern Idaho.

• Lookout Pass (I-90, ID/MT border) is a designated rest area with panoramic views and a seasonal ski area.
• Kellogg, ID (Silver Valley) offers the Silver Mountain Gondola, highest in the U.S. at 1.5 miles long.
• Washington's Columbia River Gorge (near Vantage) features the Ginkgo Petrified Forest State Park with over 50 fossilized trees.
• Anacortes Ferry Terminal provides access to the San Juan Islands; arrive 90 minutes early for vehicle boarding.

Road quality is generally excellent, with harsh winters requiring snow tires often; pack chains if traveling outside June-September. Regular rest areas exist every 30-50 miles on I-90, and Montana has open speed limits on rural interstates (up to 80 mph).

For families, the route includes the Missoula Children's Museum, the Silverwood Theme Park (north of Coeur d'Alene), and the Northwest Railway Museum in Snoqualmie. Pet-friendly accommodations are plentiful, but note that Leavenworth, WA (on the route) has restrictions on dogs in some public areas.

To combat fatigue, plan to drive no more than 8 hours per day. The Snoqualmie Pass (elev. 3022 ft) can be slick, but the Summit at Snoqualmie offers a rest stop with panoramic views. Hidden gems include the Palouse Falls in eastern Washington and the historic town of Roslyn, Washington, where the TV show 'Northern Exposure' was filmed.