Old Main Line may refer to:
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BCN Old Main Line, a canal network (and historic company name) in Birmingham, England
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BMT Lexington Avenue Line
The BMT Lexington Avenue Line (also called the Lexington Avenue elevated) was the first standard elevated railway in Brooklyn, New York, operated in its later days by the Brooklyn Rapid Transit Company, the Brooklyn–Manhattan Transit Corporat ...
, he first standard elevated railway in Brooklyn, New York
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Old Main Line Subdivision
The Old Main Line Subdivision is a railroad line owned and operated by CSX Transportation in the U.S. state of Maryland. The line runs from Relay (outside Baltimore) west to Point of Rocks, and was once the main line of the Baltimore and Ohio Ra ...
of CSX Transportation (and formerly of the Baltimore and Ohio Railroad)
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