Yup, you probably saw the coal train if all the cars looked similar. Nashua has other freight besides the coal train. Of course, it's mostly just the locals. EDNA/NAED is what supplies the Nashua yard, but you'd only see this train if you were south of Nashua.
The Nashua locals are NA-1 and NA-2. Now, I still haven't gotten it straight what the difference is, but most of the time the locals are NA-2. NA-2 works the Hillsboro Branch out to Wilton and the New Hampshire Main up to the New England Southern interchange in Manchester.
NA-1 was often used for locals that headed south, which I've heard have gone as far south as North Chelmsford. Of course the NA-1 and NA-2 designations aren't set in stone, as I've heard a train working on the Hillsboro Branch being referred to as NA-1.
As for the coal train, it usually has Norfolk Southern power or whatever NS decides to send on the train. Occasionally Guilford gets its own power on the train. I think it depends on what power is available. If the train only had two engines, it must have been a smaller load. Usually you have three 6 axle locomotives... if Guilford takes one of the normal trains, you see 4 or 5 Guilford locomotives on the head end.
The coal train goes through Manchester up to Bow, which is the town just south of Concord.
If anyone is interested in photos around Nashua of the coal train or the locals, check out this link:
Nashua City Station: Railroading Today
Matt
Nashua City Station Railroad History -
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