Stockton is a city in and the county seat of San Joaquin County in the Central Valley of the U.S. state of California. Stockton is the largest city in the county, the 11th largest city in California and the 58th largest city in the United States. Stockton's population in 2020 was 320,804. It was named an All-America City in 1999, 2004, 2015, and again in 2017. The city is located on the San Joaquin River in the northern San Joaquin Valley. It lies at the southeastern corner of a large inland river delta that isolates it from other nearby cities such as Sacramento and those of the San Francisco Bay Area.