Gravity. The owner Round Knob Hotel built it as a tourist attraction in the late 1800's
Natural
I am not sure but it was going when we were there and it was really nice. The kids ran around the outside of the wall and got soaking wet.
Then I missed something. I saw a huge man-made pool with a large mound in the middle. It was empty when I was there, so I assumed it required power. Is this the one with the stone carved benches?
Gravity
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