PH&D Railroad Historical Society P.O. Box 71 North Street, MI 48049
These maps were recently found. Here is a sample of one. We are working to have all blueprint maps permanently hosted online on another site.
Tappan to South Park 1921
This map shows the Tappan interlocking plant, the crossing or the arraignments of the Grand Trunk Western, Pere Marquette, Detroit, Bay City & Western, and Port Huron & Southern Railroads. It also has the PH&S Roundhouse and tracks to the South Park industrial area.