Site Navigation Baja California California Colorado Idaho Hawaii Nevada New Mexico Oregon Utah Washington Wyoming     Historic U.S. Highway 101 - Sonoma County Index to U.S. 101: Index Northbound Los Angeles County (#1) Los Angeles County (#2) Ventura County (#1) Ventura County (#2) Santa Barbara County (#1) Santa Barbara County (#2) San Luis Obispo County (#1) San Luis Obispo County (#2) Monterey County (#1) Monterey County (#2) San Benito County Santa Clara County (#1) Santa Clara County (#2) San Mateo County San Francisco County Marin County Sonoma County Mendocino County Humboldt County (#1) Humboldt County (#2) Del Norte County Southbound Del Norte County Humboldt County (#1) Humboldt County (#2) Mendocino County Sonoma County Marin County San Francisco County San Mateo County Santa Clara County San Benito County Monterey County (#1) Monterey County (#2) San Luis Obispo County Santa Barbara County (#1) Santa Barbara County (#2) Ventura County (#1) Ventura County (#2) Los Angeles County (#1) Los Angeles County (#2) Historic San Diego County (#1) - City of San Diego San Diego County (#2) - North San Diego County Los Angeles County Sonoma County Mendocino County Humboldt County Humboldt County/Del Norte County - Scenic Drive and Newton B. Drury Parkway Business Routes - list of all U.S. 101 business routes Ventura Santa Maria (California 135) Petaluma Santa Rosa Ukiah - decommissioned/unsigned Rio Dell (California 283) Old U.S. 101 Healdsburg - North Photo taken 05/25/06. Photo taken 05/25/06. Photo taken 05/25/06. Photo taken 05/25/06. Old U.S. 101 Healdsburg - South Photo taken 05/25/06. Photo taken 05/25/06. Photo taken 05/25/06. Photo taken 05/25/06. Photo taken 05/25/06. Photo taken 05/25/06. Page Updated October 23, 2006.