Yes you can, the campground isn't too big, but just outside of it is a botanical garden and 53 acres of explorable area.
Yes you can sale around, inside the den there is no hiking...
No you cannot hike. They do not allow people in that are not scuba diving. They are very clear and very rude about it once you arrive. If you can, they will let you pay just to walk around but not until after they have been very unprofessional. Especially the British lady there.
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