I spent some days in Berlin, working and having only the nights to enjoy the city. Dinners in a Russian restaurant and a glass of wine in an Italian winery was just an example about the opportunities you have.
First time in Winter; and we were lucky of enjoying sunny days combined with a nice snow storm during the night that dress the city with a beautiful white.
Running 13 kms around the city enables you to know new streets, stop in shops to look up at some designs, build a better map of the city in you mind and know where the people go.
Nice trip!
WordPress
Google + 
Facebook