The wonderful @organicmaps doesn't have a layer for rail lines, or otherwise highlight rail lines at zoomed-out map resolutions.

However searching for "train station" or "railway station" gives you a good-enough approximation for planning an itinerary.

Check out, for example, in the second screenshot, the suspicious lack of lines between Serbia (in the lower left) and Romania. It turns out there are effectively no public transport links across the border between the two countries. (Foot, bicycle and car options exist.)

#interrail #exploringeurope #stayingfound #traintravel