Cull Canyon Regional Recreation Area 
18627 Cull Canyon Rd.
Castro Valley, CA 94583
888-327-2757
http://www.ebparks.org/parks/cull_canyon
Park: Fish, Picnic, Walk, Water Sports
This popular swimming spot is only a short drive north from Interstate 580 on Cull Canyon Road in Castro Valley. Operated by the East Bay Regional Park District.