Randolph -- U.S. County in Illinois Population (2000): 33893 Housing Units (2000): 13328 Land area (2000): 578.416056 sq. miles (1498.090643 sq. km) Water area (2000): 18.841744 sq. miles (48.799890 sq. km) Total area (2000): 597.257800 sq. miles (1546.890533 sq. km) Located within: Illinois (IL), FIPS 17 Location: 38.079211 N, 89.796877 W Headwords: Randolph Randolph, IL Randolph County Randolph County, IL