EntityQ5050120· pop 20· linked from 106 articlesCastle HillSign in to savecensus-designated place in Contra Costa County, California, USAConnectionsSan Mateo CountyEntityUnited States Census BureauEntitycensus-designated place in the United StatesEntity2010 United States CensusEntity2020 United States CensusEntityBlackhawkEntityCaliforniaEntitySan FranciscoEntitytime zoneEntitygeographic coordinate systemEntitySan JoseEntityU.S. stateEntityOaklandEntityDaylight saving timeConceptAfrican AmericansEntityBerkeleyEntityPalo AltoEntityMarin CountyEntityCupertinoEntitySanta ClaraEntityCategoriesCensus-designated places in CaliforniaCensus-designated places in Contra Costa County, California