Problem is, the Tanzbrunnen is on the other side of the Rhine. So it´ll take you a few minutes to change from the great breweries on the one side to the venue on the other side. But there is a great "beach-club" right by the Tanzbrunnen
http://km689.rhein-terrassen.de. Re-Opening is on 1th of june. You´ll have a great look onto the Cologne Dome and the inner city from there. It´ll be great if weather is fine.
The cologne beer is famous but quite expensive. It´s a mild one and it is served in small thin glasses looking like a test tube :O)
Anyone will join in at the km689? (by the way, km689 stands for Rhine-Kilometer 689)
NP: Klaus Schulze - La Vie Electronique 13, CD 3