Bay Area Ridge Trail:

Official Web Site - Official web site for this organization that oversees the eventual creation of a trail to encircle the entire San Francisco bay region.
Marin Headlands - Part of the Golden Gate National Recreation Area, this park has many attractions: historical sites, beaches, camp sites, many hiking and multi-use trails, as well as spectacular views of San Franciso, the Pacific Ocean and the Golden Gate Bridge. It's popular to start hiking at the NW side of the GG Bridge on the Coastal Trail and hook up with the Miwok Trail.
Mt. Tamalpais State Park - The trail here at Fifield-Cahill Ridge in San Mateo County is on San Franciso water department watershed just west of San Andreas and Crystal Springs reservoirs. You may get a brochu
San Francisco Public Utilities Commission - The trail here at Fifield-Cahill Ridge in San Mateo County is on San Franciso water department watershed just west of San Andreas and Crystal Springs reservoirs. You may get a brochu
San Francisco Public Utilities Commission - The trail here at Fifield-Cahill Ridge in San Mateo County is on San Franciso water department watershed just west of San Andreas and Crystal Springs reservoirs. You may get a brochu
San Francisco Public Utilities Commission - The trail here at Fifield-Cahill Ridge in San Mateo County is on San Franciso water department watershed just west of San Andreas and Crystal Springs reservoirs. You may get a brochu
San Francisco Public Utilities Commission - The trail here at Fifield-Cahill Ridge in San Mateo County is on San Franciso water department watershed just west of San Andreas and Crystal Springs reservoirs. You may get a brochure here.