New answers tagged activities
Bubble football! It's not unique to Berlin, but it seems to be popular in Berlin and it fits the bill: it's physically demanding, absurdly fun (also, absurdly absurd), different, and probably suits someone called "soccerman" :-). Image search explains the idea better than I could: (also, there are lots of great videos, here's one). There are lots of ...
Tour E (page only in German) from Berliner Unterwelten e.V. might fit what you are looking for. It's probably only somewhat demanding, so if you aren't tired after, I guess you can climb the outside too.
Considering you liked the climbing: Hochseilgarten/high rope course in Berlin I do not know this one personally, but every similar place in Germany I know has very simple courses you can even do with small kids to hard ones that will REALLY tire you out. Prices look ok, too :).
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