Calhoun -- U.S. County in Illinois Population (2000): 5084 Housing Units (2000): 2681 Land area (2000): 253.815530 sq. miles (657.379178 sq. km) Water area (2000): 29.870828 sq. miles (77.365087 sq. km) Total area (2000): 283.686358 sq. miles (734.744265 sq. km) Located within: Illinois (IL), FIPS 17 Location: 39.168969 N, 90.653186 W Headwords: Calhoun Calhoun, IL Calhoun County Calhoun County, IL