'Warren County, IL' definitions:
Warren -- U.S. County in Illinois
From: Gazetteer 2000
Name :
Warren -- U.S. County in Illinois
Population (2000) :
18735
Housing Units (2000) :
7787
Land area (2000) :
542.520783 sq. miles (1405.122319 sq. km)
Water area (2000) :
0.646574 sq. miles (1.674618 sq. km)
Total area (2000) :
543.167357 sq. miles (1406.796937 sq. km)
Located within :
Illinois (IL), FIPS 17
Location :
40.876975 N, 90.622695 W