The Siskiyou Mountains are a coastal mountain range in the northern Klamath Mountains in northwestern California and southwestern Oregon in the United States. They extend in an arc for approximately 100 mi (160 km) from east of Crescent City, California northeast along the north side of the Klamath River into Josephine and Jackson counties in Oregon. The river forms a barrier between the watersheds of the Klamath River to the south and the Rogue River to the north.
The highest peaks in the range include Mt. Ashland (elevation 7,533 ft/2,296 m), Dutchman Peak (7,555 ft/2,303 m), and Siskiyou Peak (7,147 ft/2,178 m), all of which are in Oregon. The highest peak in California portion of the range is Preston Peak (7,309 ft/2,228 m).
Oregon Caves National Monument is located in the northern part of the range south of Grants Pass, Oregon. The Red Buttes Wilderness protects part of the range on the Oregon side of the border. Much of the range is embraced by the Rogue River , Klamath , and Siskiyou national forests. The Pacific Crest Trail follows a portion of the ridge of the range.
