I think what you're looking at is a whole lot of micro-breweries. The local beer is called koelsch, and very nice too, but there are loads of bars and restaurants that seem to offer lots of nice drinks.
You should also go and see the shrine of the three kings in the cathedral, and up the cathedral tower.
Sadly, Cologne itself shouldn't detain you for more than a day. I think the RAF helped get it like that.



