Well, the city of Sopot I live in is full of clubs, pubs or whatever you wish for. Espescially during holidays. And there's this huge beach party organized by my favourite club. So it's cool.
Trust me, you will have an awesome time in colonge. It is also close to the border of belgium and holland, and the partys are non stop for about a week!
seriously, it's a wierd place... I used to hate it because it was so ratty, but i've come to accept it. I've always wanted to study up north or in Cali so I'd be lying if i said that you should come here....