Classification: County
Located in: Illinois (IL)
Total Population (2000): 21668
Total Housing Units (2000): 8918
Land Area (square meters): 956113325
Water Area (square meters): 20361792
Land Area (square miles): 369.157434
Water Area (square miles): 7.861732
Latitude (decimal degrees): 39.083608
Longitude (decimal degrees): -90.342138
FIPS Code: 17
Place FIPS Code: 83