Salmon

River in central Idaho, USA; length 685 km/425 mi. It rises in forks in the Sawtooth and Salmon River Mountains and flows into the Snake River, southeast of Lewiston. It is noted for its sockeye, rainbow trout, and other fish, and remains undammed.

Course It flows north of Salmon, then west across the centre of the state. At Riggins it turns sharply north and flows around the Seven Devils Mountains, then southwest into the Snake. Its Middle Fork, which rises in the northern Sawtooth Range and flows 160 km/100 mi to the main river, is a fishing and whitewater boating mecca, largely in the Challis National Forest.

For its turbulence, the Salmon has been called the ‘River of No Return’, a nickname incorporated into the name of the Frank Church-River of No Return Wilderness which spreads into six national forests in Idaho and Montana. The Salmon National Forest lies along the Montana border, surrounding the river's turn to the west.