Bolinas Lagoon is a tidal estuary, approximately 1,100 acres (4.5 km2) in area, located in the West Marin region of Marin County, California, United States, adjacent to the town of Bolinas. It is a part of the Gulf of the Farallones National Marine Sanctuary and is considered to be among the possible landing spots of Sir Francis Drake on the west coast of North America in 1579.