Hercules is a city in western Contra Costa County, California. Situated along the coast of San Pablo Bay, it is located in the eastern region of the San Francisco Bay Area, about 20 miles (32 km) northeast of San Francisco. The city has a 2010 population of 24,060 according to the U.S. Census.
Upon relocating its operations from San Francisco in 1881, California Powder Works established company housing in the area that is now the city of Hercules. The city was named after the company's leading product, in turn named after the Greek demigod, Hercules.
Hercules contributed significantly to the production of explosives during both World Wars. By the Second World War, the plant had diversified to produce fertilizers and other chemical products. However, by this time the surrounding area was experiencing rapid growth as the commuter belt moved further outward from San Francisco. Study has been made of upper layer soil contamination from prior emissions of the California Powder Works operations. Eventually the facility was out-competed by foreign manufacturers, and the plant was closed in 1976. By the mid-1970s Centex Homes and other developers began to build new subdivisions and changed Hercules into a residential suburb.