Chicago Landmarks

St. Charles Air Line Bridge

St. Charles Airline Bridge, Historic American Engineering Record     Address: North of 16th St., East of Lumber St.
Year Built: 1917 - 1919 Moved to current location in 1930
Architect: Joseph B. Strauss
Date Designated a Chicago Landmark: December 12, 2007

Raised position, Historic American Engineering Record Located south of the Loop at 16th Street, the St. Charles Air Line Bridge was the world's longest and heaviest single-leaf bridge when completed. Designed by acclaimed engineer Joseph B. Strauss, the bridge is an excellent example of a "heel trunnion" bascule bridge. The span is made from heavily-bolted steel girders and plates balanced by massive reinforced-concrete counterweights. As an early example of cooperation between railroad companies, four railroads agreed to equally share construction and operating costs for the bridge. Today, the bridge is frequently used by both freight and passenger trains and is still operable. One of the most visible bridges in the city, the St. Charles Air Line Bridge can be viewed throughout the Near South from vantage points on Roosevelt Road and Clark Street.