The Salmon River flows from the Central Oregon Coast Range to the Pacific Ocean coast of northwest Oregon in the United States. About 24 miles (39 km) long, it begins and ends in Lincoln County but also flows briefly through western Polk and southern Tillamook counties. Much of its course lies within the Siuslaw National Forest.

The Central Oregon Coast Range is the middle section of the Oregon Coast Range, in the Pacific Coast Ranges physiographic region, and located in the west-central portion of the state of Oregon, United States roughly between the Salmon River and the Umpqua River and the Willamette Valley and the Pacific Ocean. This approximately 90-mile (140 km) long mountain range contains mountains as high as 4,097 feet for Marys Peak. Portions of the range are inside the Siuslaw National Forest and three wilderness areas exist as well: Drift Creek Wilderness, Cummins Creek Wilderness and Rock Creek Wilderness.