1. Kölsch beer, which is brewed according to the German Purity Law and is served exclusively in the special Kölsch bars. Traditionally, a Kölsch glass is 0.2l, but beware: the waiters in the breweries, also known as "Köbese", have a somewhat particular manner that can seem unfriendly to tourists. If a glass is empty, a fresh Kölsch is put down. You can only show that you don't want to drink any more by putting a beer mat on the empty glass.
2. The pedestrian zone in Cologne city centre lets you go for a relaxing shop without annoying fumes. Driving is prohibited on Schildergasse and Hohe Strasse, the two main shopping streets.
3. "Halver Hahn" (literally "half a chicken") is a popular snack in the local pubs and breweries. But anyone who thinks they're going to get a juicy chicken is mistaken. In Cologne, "Halve Hahn" refers to a rye roll ("Röggelchen") with butter, a large piece of Gouda, pickles, and mustard. A great snack between meals.