From San Francisco:
Take Highway 101 North across the beautiful Golden Gate Bridge. Merge onto Highway 37 East exit 460A toward Napa/Vallejo. Turn left onto Arnold Drive/CA-121, keep right at the fork to go on Arnold Drive. Arnold Drive becomes Fremont Drive, Fremont Drive becomes Sonoma Highway/CA-12/CA-121. Turn right on Duhig Road (if you reach Old Sonoma Road, you’ve gone too far), entrance is on your right.
Take Highway I-80 East toward Vallejo/Sacramento (portions toll). Merge onto CA-37 W/Marine World Parkway W via Exit 33 toward Napa. Take CA-29 exit (Exit 19) toward Napa/Downtown Vallejo. Turn right onto Sonoma Boulevard/CA-29 and continue to follow CA-29. Turn left onto Sonoma Highway/CA-12/CA-121. Turn left onto Duhig Road (which is past Old Sonoma Road). Entrance is on your right.
Take Highway I-80 West towards San Francisco. Exit onto CA-12 W/Jameson Canyon Road (Exit 39B) towards Napa/Sonoma. Turn right Napa Vallejo Highway/CA-29/CA-12 and continue to follow CA-29/CA-12. Turn left onto Sonoma Highway/CA-12/CA-121. Turn left onto Duhig Road (past Old Sonoma Road). Entrance is on your right.