Classification: County
Located in: Illinois (IL)
Total Population (2000): 17633
Total Housing Units (2000): 6690
Land Area (square meters): 984720341
Water Area (square meters): 6380583
Land Area (square miles): 380.202665
Water Area (square miles): 2.463557
Latitude (decimal degrees): 38.882098
Longitude (decimal degrees): -89.43485
FIPS Code: 17
Place FIPS Code: 5