St. Charles Air Line Bridge

St. Charles Air Line Bridge
St. Charles Air Line Bridge with an upright B&OCT Bascule Bridge just behind
Coordinates41°51′39″N 87°38′04″W / 41.86083°N 87.63444°W / 41.86083; -87.63444
Carries2 tracks of the Canadian National Railway
CrossesChicago River (south branch)
LocaleChicago, Illinois
Official nameSt. Charles Air Line Bridge
Maintained byCanadian National Railway
Characteristics
DesignStrauss Trunnion bascule lift span
Longest spanOriginally 260 feet (79 m), later shortened to 220 feet (67 m) in 1930
History
DesignerJoseph Strauss
Opened1919
Location
Map

The St. Charles Air Line Bridge is a Strauss Trunnion bascule bridge which spans the Chicago River in Chicago, Illinois.

Built as part of the St. Charles Air Line Railroad by the American Bridge Company in 1919, the bridge originally had a span of 260 feet (79 m). This bridge held the world record for longest bascule-type span until 1930, when it was shortened to 220 feet (67 m) during a relocation as a result of straightening the river channel. The chief design engineer of the original bridge was Leonard O. Hopkins.