I've seen small weddings there in the past and they sectioned off a small part of the overlook rock. Always best to call to check though.
You can go there without reservation. But other visitors will still be able to get out there. I'm not sure if they would close that down for such an event.
It would be wise to check with the park office
Free park but you should check to see what's allowed
No and no the park is free
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