NB! Boppard has a railway situated on the opposite side of the river, w/ two to three freight trains passing per hour.
Had a room w/ balcony facing the river. Room wasn't very large, but on the other hand not too small either. Room was clean. Had half pension, breakfast and dinner were both served in form of a buffet and was very good. Service in restaurant was also very good, though having mineral water at dinner turned out to be rather expensive (but they have to make their money from somewhere, right?).
Overall a very nice hotel, and everything you'll need out on the town is within walking distance. If you travel by car be prepared that finding a parking spot close to the hotel can be tricky.