The Tatoosh Wilderness is a designated wilderness in the Gifford Pinchot National Forest in Washington in the Pacific Northwest region of the United States. The wilderness protects 15,725 acres (6,364 ha) managed by the U.S. Forest Service. It was officially designated as wilderness by Congress in 1984 to protect the scenic alpine environment that complements the adjacent Mount Rainier National Park. It features Tatoosh Peak, a member of the Tatoosh Range.
Tatoosh Peak is a 6,310-foot (1,923-metre) mountain summit in Lewis County of Washington state. It is part of the Tatoosh Range which is a subrange of the Cascade Range. It is the highest point in the Tatoosh Wilderness, a protected area which is managed by Gifford Pinchot National Forest. The name tatoosh derives from Chinook Jargon which means breast. Precipitation runoff from the peak drains into tributaries of the Cowlitz River.