Considering the Gastehaus Koln in Cologne?
A VT member wrote the following comment about visiting Cologne:
Climb the Cathedral Tower by maykal
For 3DM (half that if you have a student card) you can climb the cathedral tower and look at the bells. The main reason for this, obviously, is to look at the view from the top, although 552 steps is quite a climb, especially when it is crowded, the staircase is narrow and spiral, and for the first 300 there is only one route for ascending and descending, so there are plenty of 'traffic jams'. The viewing platform is a bit cramped (but I don't suppose it can be helped, really!) but the views are spectacular. (Sorry, I've forgotten to scan my photo of the view, so you'll have to imagine it for now!!!)