Boulder River Wilderness, Protected wilderness area in Mount Baker-Snoqualmie National Forest, Washington, US.

Boulder River Wilderness is a large protected forest area in Mount Baker-Snoqualmie National Forest with densely wooded slopes and high mountain ridges. The terrain varies between river valleys and steep summits, creating a rugged landscape.

The area received protected status in 1984 when Congress passed the Washington State Wilderness Act. This designation was part of a broader effort to safeguard wilderness lands across the Pacific Northwest.

The forest here contains trees that are hundreds of years old and rarely disturbed by human activity. Visitors walk through landscapes that look much as they did long before settlement began.

The area features trails through different forest types, ranging from easier paths to challenging mountain routes. Visitors should prepare for variable weather, as elevation and tree cover can bring sudden changes throughout the day.

The old fire lookout stands on the 6,850-foot south peak of Three Fingers, the highest point in the wilderness. The sources do not give a construction date for it. The saw-toothed ridge around it includes Liberty, Big Bear, Whitehorse, Salish and Buckeye peaks, all above 5,600 feet.