Harrisburg, IL -- U.S. city in Illinois Population (2000): 9860 Housing Units (2000): 4570 Land area (2000): 6.239405 sq. miles (16.159985 sq. km) Water area (2000): 0.141101 sq. miles (0.365450 sq. km) Total area (2000): 6.380506 sq. miles (16.525435 sq. km) FIPS code: 33136 Located within: Illinois (IL), FIPS 17 Location: 37.733765 N, 88.545873 W ZIP Codes (1990): 62946 Note: some ZIP codes may be omitted esp. for suburbs. Headwords: Harrisburg, IL Harrisburg