Tom, you bring up an excellent point. Photography rail fanning is a complex endeavor depending on the terrain. I have climbed high for shots (around Glacier National Park) and have laid in wait on the flat playas of Nevada.
Mountain railfanning (Sierras) is fun and challenging lugging gear up steep trails. Perhaps my favorite is going out in bad weather. Hard rain, fog, blizzards, these all bring unique challenges - and opportunities for interesting images.
Bob - thank you for taking the time to post those links. Unfortunately I will have only one afternoon around the Manchester / Nashua area. I'm going to use maps of the area and hope for the best.
Thank you all.