trail in don edwards wildlife refuge, dumbarton bridge and coyote hills regional park in the background, fremont, san francisco

america area background bay baylands blue bridge california coyote hills delta don edwards dumbarton east fremont grass gravel green landscape levees marsh natural nobody outdoors park path plants ponds protected refuge restoration san francisco scenery scenic shadows shoreline shrubs sky slough south spring sunny sunshine swamp trail united states water waterways wetlands winding