Unusual city breaks

After our weekend in Amsterdam my friends and I have decided we need to be going somewhere for a city break at least once a year. 
The thing is, a few of us don’t want to do the usual city breaks. We’ve done Amsterdam but we want to be going to more unusual places. Some of us are throwing ideas about and it includes places such as: 

• Copenhagen 
• Stockholm
• Kraków 

Although I would love to visit these places and think they would be amazing, theyre just not unusual enough for me. I want random places that most people won’t even have heard of! 

This is where you all come in.. I was hoping you all would be able to give me ideas of places? 

Is there anywhere you have visited? Somewhere you’ve heard of? 

I keep searching, trying to find really unusual places and I’ve found a few such as:

• Olomouc
• Valletta
• Sibiu
• Wroclaw

We don’t have any specifics at all, as to where, what there is to do, weather etc. 

Please guys, any advice on where to go would be much appreciated. Leave a comment and let me know! Thanks.