If Herbert von Karajan really acted in this cultural palace - I don't know. Anyway, he was famous enough that the builder of this complex displayed a bust of him next to other honours characters.
So have a look inside and visit him, doors are wide open....
Fist of all: this is a lost place and you will realize soon, that the building is not in best conditions…. Before you enter look around that nobody can see you. Once you’re inside better be quiet. YOU are fully responsible for your doing! Take care and watch your step! If you don’t want to take the risk, forget about the cache and stay outside. Leave the kids outside.
I’ve googled a lot but I could not find anything about this sporty and cultural palace. On the right, you can see the remaining’s of a concert hall and at the opposite side a huge swimming hall with a diving platform. A pretty strange combination but worth to explore.
The coordinates were taken from google earth, but if you use the hint and spoiler you will find the cache.
Enjoy!