State Route 20 is a state highway in the northern-central region of the U.S. state of California, running east–west north of Sacramento from the North Coast to the Sierra Nevada. Its west end is at SR 1 in Fort Bragg, from where it heads east past Clear Lake, Colusa, Yuba City, Marysville and Nevada City to I-80 near Emigrant Gap, where eastbound traffic can continue on other routes to Lake Tahoe or Nevada.

The North Coast of California is a region in Northern California that lies on the Pacific coast between San Francisco Bay and the Oregon border. It commonly includes Mendocino, Humboldt, and Del Norte counties and sometimes includes Lake and two counties from the San Francisco Bay area, Marin and Sonoma.