If you're serious about coffee, you have to come to Kessel's. The place is like a mini-museum where you can see/buy coffee-related stuff, as well as drink a delicious cappuccino or espresso. Love it!
Great coffee and very friendly and helpful owners and staff. Experts in everything coffee related from machines to beans. They also offer workshops. Location is in a very nice street.
Best coffee in Bonn. They serve the best coffee and earn their money by selling coffee machines to rich people. Delicious espresso for €1,50. Good service and free water!