I enjoyed a wonderful day with Klaus seeing sights and learning about Potsdam, Sans Souci and Frederick the Great. I felt very comfortable with his driving and with him personally. Klaus’ knowledge was conveyed at just the right pace and in a relaxed manner. He was accommodating and flexible with what I was interested in and with his guiding time. Klaus also thoroughly answered my many questions about Berlin and life before, during and after the Wall. The 7 hours flew by very pleasantly indeed. I highly recommend Klaus Kannen and DriverGuides Berlin.