article: Cook County, Illinois
links: North American Numbering Plan Area code 312 Geographic Names Information System Evanston, Illinois Chicago Picasso Municipal corporation Central Daylight Time Los Angeles County, California Chicago metropolitan area Chicago Illinois Richard J. Daley Center Federal Information Processing Standard United States Geological Survey 2020 United States census List of U.S. states and territories by population Daniel Pope Cook Area code 773 Area code 847 United States Census Bureau County seat Central Standard Time U.S. state County (United States)