Martinez, CA -- U.S. city in California Population (2000): 35866 Housing Units (2000): 14597 Land area (2000): 12.251027 sq. miles (31.730013 sq. km) Water area (2000): 1.200353 sq. miles (3.108901 sq. km) Total area (2000): 13.451380 sq. miles (34.838914 sq. km) FIPS code: 46114 Located within: California (CA), FIPS 06 Location: 38.000588 N, 122.120081 W ZIP Codes (1990): Note: some ZIP codes may be omitted esp. for suburbs. Headwords: Martinez, CA Martinez