Explore Hercules local geography, civic resources and voter guides, with dated official population and registration facts for Contra Costa County.
At a glance: Hercules is an incorporated city in Contra Costa County. Population: 26,323 (California Department of Finance estimate as of January 1, 2026). Registered voters: 17,791 (California Secretary of State, as of September 4, 2026).
Hercules occupies the San Pablo Bay shoreline and the valleys rising inland from it. Its waterfront and Refugio Valley neighborhoods connect a former industrial setting with residential streets and public open space. Refugio Valley Park offers lawns, picnic tables, a gazebo, playground facilities, and courts. The Community/Swim Center on Refugio Valley Road houses the city's parks-and-recreation registration office and provides another focal point for community activities. Hercules incorporated on December 15, 1900. It is a general-law city with council-manager government, separating elected policy leadership from professional municipal administration.
The city lists it at the Community/Swim Center, 2001 Refugio Valley Road.
Yes. The city accepts reservations under its outdoor facility rules; larger gatherings require additional review.
Use Contra Costa County Elections for the current locations and voting instructions for your address.
17,791 (California Secretary of State, as of September 4, 2026).
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