The South Fork is the only major tributary that joins the mainstem from the west. The South Fork begins in Mendocino County south of Laytonville traveling west before heading almost due north, through ancient redwood forests, for a total of 105 miles, draining 689 square miles, joining the Mainstem just south of Pepperwood. It is along this tributary that highway 101 travels.
Click above on major forks of the river to learn more about each one.
| North Fork | Middle Fork | South Fork | Van Duzen | Mainstem |