Knoxville, IA -- U.S. city in Iowa Population (2000): 7731 Housing Units (2000): 3418 Land area (2000): 4.427214 sq. miles (11.466432 sq. km) Water area (2000): 0.000000 sq. miles (0.000000 sq. km) Total area (2000): 4.427214 sq. miles (11.466432 sq. km) FIPS code: 42015 Located within: Iowa (IA), FIPS 19 Location: 41.319096 N, 93.101509 W ZIP Codes (1990): 50138 Note: some ZIP codes may be omitted esp. for suburbs. Headwords: Knoxville, IA Knoxville