sentences:  It serves over 50,000 girls in 19 counties (Alameda, Butte, Contra Costa, Del Norte, Glenn, Humboldt, Lake, Marin, Mendocino, Napa, Santa Clara, San Francisco, San Mateo, Shasta, Siskiyou, Solano, Sonoma, Tehama, and Trinity).Known for it annual "Golden Gate Bridging" where Junior Girl Scouts bridging to Cadette Girl Scouts walk across the Golden Gate Bridge.This event was started in 1981 with one troop, but now has several thousand scouts involved each year, many of them from outside of the council.