Chicago
Chicago is the most populous city in the U.S. state of Illinois and in the Midwestern United States. Located on the western shore of Lake Michigan, it is the third-most populous city in the United States, with a population of 2.74 million at the 2020 census. The Chicago metropolitan area has approximately 9.62 million residents according to the 2020 census and is the third-largest metropolitan statistical area in the country and part of the fourth-largest combined statistical area in the United States, spanning 19 counties in three states and a population of nearly 10 million. Chicago is the county seat of Cook County, the second-most populous county in the U.S.
Chicago was incorporated as a city in 1837 near a portage between the Great Lakes and the Mississippi River watershed. It grew rapidly in the mid-19th century.