Chicago, officially the City of Chicago, is the third-most populous city in the United States, and also the most populous city in both the state of Illinois and the Midwestern United States. It is the county seat of Cook County.The Chicago metropolitan area, often referred to as Chicagoland is the third-largest in the U.S. Chicago has also been called a global architecture capital and considered one of the most important business centers in the world.Take a look at these photos to see what street scenes of Chicago looked like in the early 1980s.