A Century of Progress International Exposition, also known as the Chicago World's Fair, was a world's fair held in the city of Chicago, Illinois, United States, from 1933 to 1934. The fair, registered under the Bureau International des Expositions (BIE), celebrated the city's centennial. Designed largely in Art Deco style, the theme of the fair was technological innovation, and its motto was "Science Finds, Industry Applies, Man Conforms", trumpeting the message that science and American life were wedded. Its architectural symbol was the Sky Ride, a transporter bridge perpendicular to the shore on which one could ride from one side of the fair to the other.

A transporter bridge, also known as a ferry bridge or aerial transfer bridge, is a type of movable bridge that carries a segment of roadway across a river. The gondola is slung from a tall span by wires or a metal frame. The design has been used to cross navigable rivers or other bodies of water, where there is a requirement for ship traffic to be able to pass. This has been a rare type of bridge, with fewer than two dozen built. There are just twelve that continue to be used today, including one converted into a lift bridge and one designed as, but not yet operating as, a transporter bridge.