The Monterey Bay National Marine Sanctuary (MBNMS) is a federally protected marine area offshore of California's Big Sur and central coast in the United States. It is the largest US national marine sanctuary and has a shoreline length of 276 miles (444 km) stretching from just north of the Golden Gate Bridge at San Francisco to Cambria in San Luis Obispo County. Supporting one of the world's most diverse marine ecosystems, it is home to numerous mammals, seabirds, fishes, invertebrates and plants in a remarkably productive coastal environment. The MBNMS was established in 1992 for the purpose of resource protection, research, education, and public use.

The Central Coast is an area of California, roughly spanning the coastal region between Point Mugu and Monterey Bay. It lies northwest of Los Angeles and south of the San Francisco Bay Area, and includes the rugged, rural, and sparsely populated stretch of coastline known as Big Sur.