As of 2000 the CSX Plymouth/Lansing Subdivisions connect Detroit to Western Michigan for the CSX. It ties the Detroit area to Western Michigan and Chicago. Built in the late 1800's this line operated as the Detroit, Grand Rapids and Western RR, formerly the Detroit, Lansing and Northern RR. The DGR&W's original mainline became the East-West route for the Pere Marquette RR in 1900 after its merger with the Flint & Pere Marquette.
On the Pere Marquette the mainline from Plymouth to Grand Rapids became the Plymouth Division. On the C&O it became the Plymouth Subdivision of the Michigan District. This is now part of the CSX Detroit Division, connecting the Detroit and Saginaw Subs at Plymouth with the Lansing Sub at Trowbridge Jct.
6 CSX Manifests polish the rails daily plus 10 to 12 CP/Soo run-through trains that run between Detroit and Chicago. Other traffic includes daily unit Coal/Grain trains as required.