We think Berlin is a nice and interesting city with an easy going atmosphere. This time it was very hot and we wondered what the average Berliner would do to fight the heat. We heard that a lot go swimming in one of the many lakes outside the city centre. We chose the Schlachtensee. Big lake, clean water, little private Sandy beaches, a relaxed atmosphere, we saw families and couples, Young and old. It is all for Free and near the U-bahn. Lovely Biergarten and beautiful restaurant nearby. But we had a picknick with us so don 't know about those.