Yesterday I visited the ancient westgerman city of Trier.
I took the train, I had to switch trains at Koblenz and to my suprise the train from Koblenz to Trier was a train operated by the CFL (Chemins der Fer Luxembourgeois) the state railway of the Grad Duchy of Luxembourg. Trier is pretty close to the border. Here is the complete passanger rail map of the small country and you can see that their trains cross to the neigbouring nations of Germany, France and Belgium.