About Castro Valley, California

Castro Valley is a census-designated place (CDP) in Alameda County, California, United States. As of the 2000 census, it is the fifth most populous unincorporated area in California, and the twenty-third in the United States. [citation needed] The population was 61,388 at the 2010 census.

News from Castro Valley

Castro Valley Facts

  • Population Total: 61388
  • Square Miles: 16.635
  • Area Code: 510
  • Elevation: 164
  • Postal Codes: 94546, 94552
  • Timezone: Pacific Standard Time