San Ardo, formerly known as San Bernardo (Spanish for "St. Bernard"), is an unincorporated community and census-designated place (CDP) in Monterey County, California, United States.

[4] San Ardo is located 18 miles (29 km) southeast of King City[6] at an elevation of 449 feet (137 m).

[7] San Ardo is near the point where the broad Salinas Valley has its southeastern terminus and pinches out within the converging portions of the California Coast Ranges, including the Santa Lucia Mountains on the west and the Cholame Hills and the Diablo Range on the east.

According to the United States Census Bureau, the CDP has a total area of 0.4 square miles (1.0 km2), all of it land.

[3] The Salinas River flows northward along the west side of the community.

This region experiences warm (but not hot) and dry summers, with no average monthly temperatures above 71.6 °F.

[8] The huge San Ardo Oil Field is about 5 miles (8 km) south of town.

Much of the local economy is based on agriculture (including farming and ranching), and servicing the oil field.

There were 167 housing units at an average density of 371.5 per square mile (143.4/km2).