My experience is that there is an entry fee for parking within the park if you enter the main entrance/gate. However there is some parking available on the street for free (State College). Check parking signs on street for any additional restrictions.
No entry fee. But there is parking fee if you drive in.
I have been there when there isn't. One time they had Big Bad Voo Doo Daddy free at the park and parking was free. Another time they had Dead Man's Party, a Oingo Bingo cover band and there was an admission. They go full out on their events sometimes. Food trucks, radio stations (KROQ, JACK), even alcoholic drinks.
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