[A pedant writes] It's always a tricky decision as to whether to use English or German names, but surely you need to be consistent: München and Köln or Munich and Cologne
Loads of great cities in Germany, I've done a lot of travelling there. Berlin's my favourite but Munich, Hamburg and Cologne are fantastic too. Dortmund is great for a boozy weekend and Weimar if you want a cultural experience. The only places that I found pretty dull were Hanover and...
Berlin for me - never ceases to fascinate
Runner-up is Budapest. First visited it when it was in the Eastern bloc and have been back many times since
Favourite in the UK is Bristol. Reminds me a bit of Brighton - once even thought of living there