We visited for Köln v Hannover. Sitting in the south stand block S16. Navigating from Düsseldorf was fairly easy and only had to ask the locals for directions once. There's a special train that runs to the stadium from Cologne , match ticket includes travel on this. The stadium looked a bit industrial from outside and the queues were huge, but moved along very fast. Just under 49k attendence was impressive for a team bottom of the league. The atmosphere in the ground was fantastic, and miles better than most you see in England. You can also spend cash in the ground rather than loading a prepay card like at other bundesliga grounds. Keep your eyes out for the beer man doing the rounds, saves missing any of the game.