My mother and I went on the night tour with Birgit. We had walked all day and weren't sure how our legs would hold up for 3 more hours of biking but Birgit kept us occupied with so many sights and a lot of interesting information we didn't feel tired at all, it was excellent! We were able to see so much of the city that we would never have seen otherwise. Completely recommend this tour!! Thanks Birgit!!