Northwest of San Francisco and east of San Rafael, the 1,650 acre China Camp State Park has over 10 miles of narrow singletrack trails through wooded hills overlooking San Pablo Bay. The Bay View Trail and the Shoreline Trail can be combined to form the 9.4 mile singletrack loop. Plus, there are numerous side fire roads to explore.
To reach the mountain biking trailhead from San Fran, head north on US101 to San Rafael and use Exit #454B. Head northeast on North North San Pedro Road for 3.1 miles into China Camp State Park. Park along the road near Back Ranch Campground. The Bay View Trail starts climbing up from the entrance kiosk and runs for 7 miles to the Shoreline Trail for the return trip. Make sure to pay for your daily use fee permit.
Tip - After a long mountain bike ride at China Camp State Park, make sure to head over to the Gestalt Haus in Fairfax for a cold drink!