Napa-Sonoma Marshes Wildlife Area

The Napa Sonoma Marsh is a wetland at the northern edge of San Pablo Bay, which is a northern arm of the San Francisco Bay in California, United States. This marsh has an area of 48,000 acres, of which 13,000 acres are abandoned salt evaporation ponds. The United States Government has designated 13,000 acres in the Napa Sonoma Marsh as the San Pablo Bay National Wildlife Refuge.