It starts innocently enough ..

with the regular old commuter rail heading west on the Fitchburg line.

SUDDENLY ...

trying to sneak by unnoticed is the Pan Am business (??) train!!

OMG !!! this is exciting!

Will one or more of you hard core train observers fill us all in about what this train is "made of" and anything else you want to share.

This is at Ayer, Massachusetts, just west of downtwon Ayer.

Done