Classification: County
Located in: Illinois (IL)
Total Population (2000): 39678
Total Housing Units (2000): 15297
Land Area (square meters): 2703325383
Water Area (square meters): 4333369
Land Area (square miles): 1043.75981
Water Area (square miles): 1.673123
Latitude (decimal degrees): 40.903217
Longitude (decimal degrees): -88.565955
FIPS Code: 17
Place FIPS Code: 105