Classification: County
Located in: Illinois (IL)
Total Population (2000): 39018
Total Housing Units (2000): 18105
Land Area (square meters): 1067269330
Water Area (square meters): 50043890
Land Area (square miles): 412.07501
Water Area (square miles): 19.322055
Latitude (decimal degrees): 37.974494
Longitude (decimal degrees): -88.955152
FIPS Code: 17
Place FIPS Code: 55