De or het sportaccommodatie?

The correct Dutch article is:

de sportaccommodatie

Rule Words ending in -tie and -sie: almost always de. See the rule

How to use sportaccommodatie

the sportaccommodatiede sportaccommodatie
this sportaccommodatiedeze sportaccommodatie
that sportaccommodatiedie sportaccommodatie
our sportaccommodatieonze sportaccommodatie
your sportaccommodatiejouw sportaccommodatie
every sportaccommodatieelke sportaccommodatie
which sportaccommodatie?welke sportaccommodatie?
a big sportaccommodatie / the big sportaccommodatieeen grote sportaccommodatie, de grote sportaccommodatie