Pere Marquette Railroad - Mainline
The Pere Marquette Railway came to being in 1900 via the merger of several Michigan based railroads the most notable were;
Flint & Pere Marquette Railway
Detroit, Lansing & Northern Railway
Chicago & West Michigan Railroad
It encompased many areas of Michigan and operated in Toledo Ohio, Chicago Illinois and Ontario Canada. The largest portion of it's operation was from Detroit to Grand Rapids Michigan. The Fort Street Union Depot the heart of it's Detroit area passenger service was built in 1893 and operated until 1971. The Pere Marquette operated as such until 1947 when it merged into the C&O Railroad.
Pennsylvania Railroad - PRR
The PRR started it's humble beginings in 1846 and grew via many mergers into the largest railroad by traffic & revenue in the U.S. It operated limited freight and passenger service in and out of the Detroit area starting in 1920. The well known "Red Arrow" passenger trains utilized the Fort Street Union Depot in Detroit until 1959.