Filming Of Transformers 3', Chicago, United States

Chicago is the largest city in both Illinois and the Midwest, and the third most populous city in the United States, with over 2.8 million living within the city limits. Its metropolitan area, commonly named "Chicagoland", is the 26th most populous in the world, home to an estimated 9.7 million people spread across the U.S. states of Illinois, Wisconsin, and Indiana. Chicago is primarily located within Cook County, with the exception of a small northwestern portion of the city at O'Hare International Airport that is located within DuPage County.
Chicago was founded in 1833, near a portage between the Great Lakes and the Mississippi River watershed. The Potawatomi were forcibly removed from their land following the Treaty of Chicago. The city became a major transportation and telecommunications hub in North America. Today, the city retains its status as a major hub, both for industry and infrastructure, with O'Hare International Airport being the second busiest airport in the world. In 2008, the city hosted 45.6 million domestic and overseas visitors.