From SFBC:
Join Ybike for some or all of a 30 and 50-mile loop ride from the Presidio to McNears Beach, a Marin County Park near China Camp State Park. Route follows a string of multi-use paths through Marin County (past the Sausalito and Larkspur ferry terminals) through the recently completed Cal Park Bike Tunnel. Info and Registration: ybike.org/mcnears.
