And is there a better way to say "indoor" for the Indoor-Skatepark bit?
Probably not any more. If that venue calls itself 'Indoor Skatepark' then every native speaker will probably use exactly that name.
Most indoor venues used to be called
Hallen-something (e.g. indoor swimming pool = Hallenbad; indoor soccer = Hallenfußball; etc)
However, with Skatepark that doesn't work well because 'Park' is a decidedly outdoor thing. Therefore, Skatepark-Halle is possible and understandable but it sounds strange.
Alternatively you could use 'überdacht' to express the indoor aspect, i.e. 'der überdachte Skatepark'. But for younger people this might sound odd too because most indoor stadiums are now called 'Indoor Stadion', rather than 'überdachtes Stadion'.
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