The Chicago and North Western Railway's Kinzie Street railroad bridge (also known as the Carroll Avenue bridge or the Chicago and North Western Railroad Bridge) is a single leaf bascule bridge across the north branch of the Chicago River in downtown Chicago, Illinois. At the time of its opening in 1908 it was the world's longest and heaviest bascule bridge. The previous bridges on the same site included a pedestrian span that was the first bridge across the Chicago River; a second bridge that served as Chicago's first railroad bridge; and a third bridge that was one of the first all-steel spans in the United States.

The Chicago Sun-Times, the last railroad customer to the east of the bridge, moved their printing plant out of downtown Chicago in 2000, and the bridge has been unused since. It was designated a Chicago Landmark in 2007. The bridge is lowered once a year and inspected by crew driving a Hi-Rail truck, and is still in "active" status