Madison -- U.S. County in Missouri Population (2000): 11800 Housing Units (2000): 5656 Land area (2000): 496.731267 sq. miles (1286.528020 sq. km) Water area (2000): 0.869996 sq. miles (2.253278 sq. km) Total area (2000): 497.601263 sq. miles (1288.781298 sq. km) Located within: Missouri (MO), FIPS 29 Location: 37.503750 N, 90.312535 W Headwords: Madison Madison, MO Madison County Madison County, MO