Head up to Mendocino, go north across Golden Gate Bridge, 1 to Mt Tam, up & over, or various other routes out to the coast - Lucas Valley? Route 128 either going up, coming back, or both, is a must.
http://maps.google.com/maps?source=i...-8&sa=N&tab=wl - zoom in to check out...
Check in Local Clubs/MOB/Resources, scroll down for some other ideas...
Favorite Rides
Tam Loop, With Chileno Valley Rd & Lucas Valley Rd: 108 miles
Longer Marin/Sonoma loop
Alice's Loop, with CA-9 and Pescadero Rd: 130 miles
Mines Rd, with Niles Canyon: 102 miles