The Interstate 74 Bridge, originally known as the Iowa-Illinois Memorial Bridge, is a bridge that crosses the Mississippi River and connects Bettendorf, Iowa and Moline, Illinois. It is located near the geographic center of the Quad Cities. The first span opened in 1935 as a toll bridge. In 1959 an identical twin span was added to satisfy increased traffic. The twin spans were upgraded to carry interstate traffic in the mid-1970s. In 2005, an average of 77,800 vehicles crossed the I-74 bridge daily, making it by far the most traveled bridge in the Quad Cities. Both the Interstate 80 and 280 bridges are up to Interstate standard, while the Interstate 74 bridge has two narrow lanes, no shoulder, and a 50 mile-per-hour (80 km/h) speed limit.
The I-74 Corridor Study is underway to study replacing the bridge with a larger one with 4 lanes in each direction.