Greater Portland Area - Portland Traction Company
Thanks to Craig Bass for the information and photo on this page.
Portland Traction Co. enginehouse.  Photo from August 1981.
The Portland Traction Company was an interurban and local transit company that served the greater Portland area.  Though the last rail passenger service ended in 1958, certain lines remained in service serving freight customers for some years afterward.

For more information, with this photo (and several more), a detailed narrative/history and a map, go to
http://cbassweb.com/railroads/ptc/index.htm