If you arrive after the park is closed, there is an after-hours gate located at the main entrance off of Frank Parkway that you can get into even if the main park gate is locked. If it's too late that the campground staff has gone home, just go ahead and set up camp and the staff will talk to you in the morning.
Angie is right. You have to call because the park gate will be closed otherwise..or a big risk anyway
Call the park office & let a park ranger know what time you will be arriving. They should let you in.
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