What do you like best?

For me, I love to train-watch in the mountains around Denver!! Also I like desert train-watching too!!

I’m with you–I like both mountain and desert. Also the California Coast between Atascadero and San Luis Obispo, even though the old ex-SP Coast Line isn’t that heavily trafficked, anymore (except for Amtrak and a few UP freights). However for me, the romance of railroading still remains on Donner and Tennessee passes.
Tom [:D]