You can go to the beach without camping. Yes once you pay at the entrance you can use the park. I think the extra charges are to rent boats, and camping. No reservations need for daytime use. Need reservations for camping, and renting boats.
You just pay to get into the park, then you can use the entire park & both beaches!
You can go without a reservation.
Of course, all the beauty of ASP is available to everyone.
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