I'm off to Koblenz for a short break next weekend, wife wants to go visit the Christmas market there, we are staying not far from the station.
I will be driving rather than take the train, catching the train here is a bit of a pain in the rear and quite expensive, It's a 90km drive to the station that connects with the line to Köln.
I have both the routs too, so thanks for the heads up, a 288MB update downloading now...