The Shore Line Subdivision is a railroad line owned and operated by Grand Trunk Western Railroad (GTW), a subsidiary of Canadian National (CN), which connects the cities of Detroit, Michigan and Toledo, Ohio, paralleling the shore of Lake Erie.
The Shore Line Sub is single track with the parallel Tunnel Industrial track beginning at Milwaukee Junction at MP 54.8 south to Vinewood Interlocking at MP 51.2 where the Tunnel Industrial ends.
The line continues past West Detroit junction at MP 50.1 on trackage rights over a Norfolk Southern (NS) railway (originally the Wabash Railroad mainline) to Delray Interlocking at MP 47.8.
The line continues along the NS railway until it crosses the River Rouge picking back up on its own trackage.
From that time forward the Shore Line Sub has been lengthened to include territory that was once part of the Wabash Rwy from Rouge Bridge to West Detroit, as well as territory that was part of the GTW Mount Clemens Subdivision.