CSX Plymouth Subdivision

The CSX Plymouth Subdivision is a freight railroad line in the U.S. state of Michigan. It connects the Plymouth Diamond at milepost CH 24.5 to Grand Rapids at CH 148.1, passing through the Lansing metropolitan area en route. Other towns served include Brighton, Howell, Williamston, Grand Ledge, and Lake Odessa. Operationally, it is part of the CSX Chicago Division, dispatched from Calumet City, IL.

Construction of what is now the 124-mile CSX Plymouth Subdivision was attempted in the 1860s by a succession of short-lived and undercapitalized railroad companies, including the Detroit and Howell Railroad (organized 1864), the Ionia and Lansing Railroad (organized 1865), the Howell and Lansing Railroad (organized 1868), and the Detroit, Howell and Lansing Railroad (created by merger 1870). Principal construction on the Lansing-Detroit segment was completed by the Detroit, Lansing and Lake Michigan Railroad (created by merger 1871), with operations commencing on August 31, 1871.

In 1896 control of this east-west mainline through the state capital passed to the Detroit, Grand Rapids and Western Railroad (DGR&W), and subsequently by merger to the Pere Marquette Railroad (later Railway) in 1900. Though never among the most profitable railroads, the Pere Marquette persevered until it merged with the Chesapeake and Ohio Railroad (C&O) in 1947. The C&O became part of the Chessie System in 1972, and was absorbed into CSX Transportation in 1987.