Once you see the home videos of its creator doing the work, the mystery evaporates. Nothing supernatural or advanced for its own time. Just simple, well-known tools and engineering.
The structures aren’t ancient, but the same sort of paleobabbling “explanations” used for Coral Castle are used for those structures, too. Enjoy!
Kudos to Chris White once again. Chris is the guy who created the free, three-hour documentary, Ancient Aliens Debunked, of which I was a part. Give that a watch, too (nearly five million people already have).