My list (this is probably incompltete): Union Pacific Canadian Pacific (CPKC) Canadian National Norfolk Southern CSX Transportation Amtrak Massachusetts Bay Transport Authority Metro North (MTA) CTrail Wiscasset Waterville & Farmington Sandy River & Rangley Lakes Maine Narrow Gauge Central Maine & Quebec Maine Eastern Midcoast Railservice Pan AM Railways St. Lawrence & Atlantic (G&W) Valley Railroad (VALE) Boothbay Central Railway Downeast Scenic Railroad Edaville Railroad Berkshire Scenic Railroad New Jersey Transit Seashore Trolley Museum
