The Siskiyou Wilderness is a federal wilderness area designated by the passage of the California Wilderness Act of 1984. Originally, the land area was 153,000 acres (620 km2) The Northern California Wild Heritage Act of 2006 added 30,122 acres (121.90 km2) for the current total of 182,802 acres (739.77 km2). All of the wilderness is in Northern California and is managed by the U.S. Forest Service. The wilderness spans three national forests: the Rogue River–Siskiyou, the Klamath, and the Six Rivers.

The Rogue River–Siskiyou National Forest is a United States National Forest in the U.S. states of Oregon and California. The formerly separate Rogue River and Siskiyou National Forests were administratively combined in 2004. Now, the Rogue River–Siskiyou National Forest ranges from the crest of the Cascade Range west into the Siskiyou Mountains, covering almost 1.8 million acres (7,300 km2). Forest headquarters are located in Medford, Oregon.