Me and my friend are traveling, starting 21July, we're going to italy first, this is just a small holiday, he's got relatives there we're going to see, just to relax but after that we plan on going to Slovenia, Croatia, Hungary, Poland, Czech/prague Germany, Belguim and Holland.
What would you guys suggest the best places to see, we're both into architecture and maybe 1 or 2 world war sites. We've both already been to Ann Franks house in Holland, had a tour around Auschwitz and a few more obvious places on previous holidays.
This time we're backpacking it and only staying in each country around 3/4 days in each, so abandoned places, sites "off-the-beaten-track", less known sites. We're thinking about Hohenzollern castle and the black forest in Germany, but thought Reddit might help?