It depends on why you are following the route (which by the way starts way back in Europe (I think Copenhagen is even on it) certainly Christchurch, Brugges and Trier are on it).
If you are following the route for a bike journey I think you need …
You go somewhere warm which means Portugal, Spain (real Europe), Morocco, Caneries, (not really europe but very on the edge)
You go somewhere with loads of cheap warm spas which means Iceland, Hungary, Czech Rep, Eastern Germany
The German's have kinda tidied up since then, so you might like to look at the holocaust memorial in Berlin. Most towns will have a war memorial. There are more of these sort of things in France with many towns having a museum