You probably know that Mr S is German and I 've lived and worked there. Düsseldorf is nice.Loads of bars,restaurants and great shopping. The old town is lovely ,same with Cologne ,the old town and the Cathedral and loads of museums and galleries .A Rhine cruise is great for seeing stuff. Nice one from Düsseldorf to Rüdesheim.Stops off at lots of lovely old towns where you can overnight if you want to and of course the scenery is superb,castles,vineyards,the Lorelei etc.