The river originates at Sonora Peak, in the Sierra Nevada in Alpine County, California. The headwaters of the river are in the Carson-Iceberg Wilderness of the Humboldt-Toiyabe National Forest. It flows north through a U-shaped glacial canyon, dropping over Carson Falls, then continues to the Silver King Valley, where it meets Silver King Creek and turns northwest, flowing to Centerville Flat where it is joined by Silver Creek and turns north. Between here and Markleeville, California the river canyon is followed by parts of SR 4 and SR 89, the Alpine State Highway. At Markleeville it receives a major tributary, Markleeville Creek, before flowing north into Douglas County, Nevada. In Nevada the river enters the agricultural Carson Valley and passes through the Washoe Indian Reservation, past Dresslerville, Gardnerville and Minden. It joins with the West Fork Carson River on the western edge of the valley, near Genoa to form the Carson River. Below this confluence the Carson River continues to its eventual terminus in the Carson Sink in Churchill County, Nevada.