San Gregorio State Beach, State beach in San Mateo County, California, United States

San Gregorio State Beach lies just west of the junction of State Routes 1 and 84, south of Half Moon Bay. San Gregorio Creek widens into a small freshwater lagoon behind a sand berm that usually blocks the creek mouth, so the water seeps underfoot into the Pacific; in the rainy season the creek often cuts through the berm and flows straight into the ocean. The photograph shows a broad flat expanse of tan sand crossed by a shallow dark stream edged with white foam, with a driftwood log and scattered debris near the base of the green hills on the left.

A stone marker at the beach commemorates the camp of Gaspar de Portolà's expedition, which stayed three days in 1769 to rest and treat the sick while searching for Monterey Bay. The party failed to find it and went on to discover San Francisco Bay. The site is California Historical Landmark 26; the plaque on the marker is now missing.

The creek was historically a coho salmon spawning site, and the Department of Fish and Game is considering restocking it with coho to improve salmon fisheries south of San Francisco. The beach is also a self-registered fee area, with a kiosk staffed during summer months.

Facilities include restrooms and picnic tables, and the park is a self-registered fee area with a kiosk staffed during summer months. Dogs are not permitted on the beach because it serves as nesting habitat for the western snowy plover. The beach lies just west of the intersection of State Route 1 and State Route 84.

The beach is listed as California Historical Landmark 26, and a stone marker with a plaque (now missing) stands where Gaspar de Portolà's expedition camped in 1769. The party rested there for three days to treat their sick before continuing north and finding San Francisco Bay instead of Monterey Bay.