Chicago metropolitan area

The Chicago metropolitan area, also referred to as the Greater Chicago Area and Chicagoland, is the largest metropolitan statistical area in the U.S. state of Illinois, and the Midwest, containing the City of Chicago along with its surrounding suburbs and satellite cities. Encompassing 10,286 square mi (28,120 km2), the metropolitan area includes the city of Chicago, its suburbs and hinterland, that span 13 counties across northeast Illinois and northwest Indiana. The MSA had a 2020 census population of 9,618,502 and the combined statistical area, which spans 19 counties and additionally extends into southeast Wisconsin, had a population of nearly 10 million people. The Chicago area is the third largest metropolitan area in the United States and the fourth largest metropolitan area in North America (after the metro areas of Mexico City, New York City, and Los Angeles), and the largest in the Great Lakes megalopolis. Its urban area is one of the forty largest in the world.
According to the 2020 Census, the metropolitan's population is approaching the 10 million mark. The metropolitan area has seen a substantial increase of Latin American residents on top of its already large Latino population, and the Asian American population also increased according to the 2020 Census. The metro area has a large number of White, Black, Latino, Asian, and Arab American residents, and also has Native American residents in the region, making the Chicago metropolitan area population truly diverse. The Chicago metropolitan area represents about 3 percent of the entire US population.
Chicagoland has one of the world's largest and most diversified economies. With more than six million full and part-time employees, the Chicago metropolitan area is a key factor of the Illinois economy, as the state has an annual GDP of over $1 trillion. The Chicago metropolitan area generated an annual gross regional product (GRP) of approximately $700 billion in 2018. The region is home to more than 400 major corporate headquarters, including 31 in the Fortune 500 such as McDonald's, United, and Blue Cross Blue Shield. With many companies moving to Chicagoland, and many current companies expanding, the area ranked as the nation's top metropolitan area for corporation relocations and expansions for nine consecutive years, the most consecutive years for any region in the country.
The Chicago area is home to a number of the nation's leading research universities including the University of Chicago, Northwestern University, the University of Illinois at Chicago, DePaul University, Loyola University, and the Illinois Institute of Technology (IIT). The University of Chicago and Northwestern University are consistently ranked as two of the best universities in the world.
There are many transportation options around the region. Chicagoland has three separate rail networks; the Chicago Transit Authority (CTA), Metra, and the South Shore Line. The CTA operates elevated and subway lines that run primarily throughout the city, Downtown Chicago, and into some suburbs. The CTA operates some of its rail lines 24 hours a day, every day of the year, nonstop service, making Chicago, New York City, and Copenhagen the only three cities in the world to offer some 24 hour rail service running nonstop, everyday throughout their city limits. The Metra commuter rail network runs numerous lines between Downtown Chicago and suburban/satellite cities, with one line stretching to Kenosha, Wisconsin, which is part of the Chicago metropolitan area. The interurban South Shore Line runs between Downtown Chicago and the northwest Indiana portion of the metropolitan area. In addition, Amtrak operates Union Station in Downtown Chicago as one of its largest rail hubs, with numerous lines radiating to and from the station.
CTA bus routes serve the city proper, with some service into the suburbs. Pace bus routes serve the suburbs, with some service into the city. In addition, numerous CTA bus routes operate 24 hours a day, nonstop.