A FlyerTalk Posting Legend
Join Date: Sep 2009
Location: Minneapolis: DL DM charter 2.3MM
Programs: A3*Gold, SPG Plat, HyattDiamond, MarriottPP, LHW exAccess, ICI, Raffles Amb, NW PE MM, TWA Gold MM
Posts: 102,617
To go off the list, I love Copenhagen. If you don't want to stay there the whole time, take a ferry or the new tunnel/bridge to Malmo and then to to Lund for a day and night. Stockholm, Oslo, and Bergen are also nice, but you would need to fly from Copenhagen.
There are also some interesting places to visit in Germany. Go to Munich and then take the train (gorgeous scenery) to Salzberg for a few days.