Chicago

Chicago is the largest city in Illinois and the county seat of Cook County. Situated on the western shore of Lake Michigan, it is the third-most populous city in the United States, with 2.74 million residents at the 2020 census, and anchors a metropolitan area of more than 9 million people. Incorporated in 1837 near a key portage between the Great Lakes and the Mississippi River watershed, Chicago grew rapidly during the 19th century and became a major inland transportation and commercial hub.

The city’s development was shaped by major engineering and urban projects, including river and harbor improvements, rail expansion, and rebuilding after the Great Chicago Fire of 1871, which destroyed large parts of the city but did not halt its growth. Chicago later became influential in architecture and urban planning through the Chicago School and the City Beautiful movement, helping pioneer the steel-framed skyscraper.

Today, Chicago is an international center for finance, commerce, industry, education, technology, telecommunications, and transportation. It is especially important in derivatives trading and is home to O'Hare International Airport, one of the world’s busiest airports. The city also has a diversified economy and a major tourist sector.

Chicago is widely known for its cultural life, including jazz, blues, house music, theater, comedy, and cuisine. It is home to institutions such as the Chicago Symphony Orchestra, the Lyric Opera of Chicago, the Art Institute of Chicago, the University of Chicago, Northwestern University, and University of Illinois Chicago. Major professional sports teams and events, including the Chicago Marathon, are also part of the city’s identity.