In the Duna there is an Island called the "Ship Factory" because there was once a ship factory there (what a surprise) but there are lots of nice places, parks and such. It is most famous for the big yearly music festival that is held there in every august, people from all over Europe come there, but there are other things held too.
This weekend there were places for climbing, for solving logical dilemmas, labyrinths, and the combination of those:
Christopher enjoyed it tremendously. As always my feeling (that he behaves much better if he is with me than if he is with P. or the both of us) was reinforced. We got home utterly exhausted, but it was worth it.