Williamson County, Illinois Basics:
Williamson County Illinois - Government Site
Population: 66,714
Area: 420 square miles
County seat: Marion
Area code(s) in use: 618
Time zone: CST
High school graduate or higher: 88.4%
Bachelor's degree or higher: 21.7%
Median household income: $41,596
Persons in poverty: 16.5%
Home ownership rate: 71.3%
Mean travel time to work: 20.3 minutes
Adjacent counties:
Franklin Jackson Johnson Pope Saline Union