California Highway 1
Your go-to sections are south of San Francisco between Pacifica and Santa Cruz and north of the Golden Gate Bridge in Marin County. Getting south is pretty easy: find Interstate 280 and take the Pacifica exit south. Getting north will require navigating some San Francisco traffic but generally you can follow the Golden Gate Bridge signs, then look for the Highway 1 signs once you hit Marin County.
The Marin section is spectacular, but the traffic and hair-pin turns make the drive hair-raising and nerve-racking. All the more reason to ride south: the 60-mile stretch from Pacifica to Santa Cruz passes a string of state beaches for parking and picnicking. The main challenge will be keeping your eyes on the road amid the stunning cliffs at the nation's edge.
The town of Pescadero is a great stop along the way -- Duartes Tavern is a Bay Area favorite. At Santa Cruz you might as well turn back and see the whole route from the other direction. If you're in more of a hurry, stay on Highway 1 through town and head north on Highway 17 and take I-280 north from San Jose.