This is the 13171st most frequent Polish word.
ogólnopolskich
"Ogólnopolskich" means "nationwide" or "across Poland" in English.
The word 'ogólnopolskich' is used here as an adjective describing the scope (nationwide) of cultural events.
W gazecie znalazłem artykuł o ogólnopolskich wydarzeniach kulturalnych.
In the newspaper, I found an article about nationwide cultural events.
The word 'ogólnopolskich' is here in its adverbial use to associate the activity's interest level to a national scope.
Ten festiwal cieszy się zainteresowaniem na poziomie ogólnopolskim.
This festival enjoys interest at a nationwide level.
The word 'ogólnopolskich' is used as an adjective modifying the noun 'competitions' to indicate these sports competitions take place on a national level.