St. Charles Air Line Bridge

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

St. Charles Air Line Bridge
St. Charles Air Line Bridge with an upright B&OCT Bascule Bridge just behind
Coordinates	41°51′39″N 87°38′04″W
Carries	2 tracks of the Canadian National Railway
Crosses	Chicago River (south branch)
Locale	Chicago, Illinois
Official name	St. Charles Air Line Bridge
Maintained by	Canadian National Railway
Characteristics
Design	Strauss Trunnion bascule lift span
Longest span	Originally 260 feet (79 m), later shortened to 220 feet (67 m) in 1930
History
Designer	Joseph Strauss
Opened	1919
Location

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.

Photo gallery

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  Chicago landscape with a boat
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  St. Charles Air Line Bridge, May 17, 2022.

See also

• The adjacent B&OCT Bascule Bridge, with more information about the history of both bridges
• List of bridges documented by the Historic American Engineering Record in Illinois

Further reading

• "Counterweight Repair of Historic St. Charles Air Line Bridge" (PDF). Concrete Repair Bulletin. 28 (6): 9–13. November 2015.

External links

• Historic American Engineering Record (HAER) No. IL-157, "St. Charles Air Line Bridge"
• Historic Bridges of Michigan and Elsewhere