There was a website (now gone) about Coral Castle years ago by somebody called MikeyNed. He had close up pictures of the stones, showing nails sticking out of them, impressions of automobile leaf springs in many of the slabs, and glass bottles embedded in other stones, and "puddling" on the surface of many of them as well.
He got very upset when I said that it looked like they were made out of concrete instead of the "melted stone" theory.
I figure the guy that built the castle chipped the rock out of the ground, made a concrete out of it, and cast it into forms (the leaf springs look like they were inserted at the edges, and a sledge hammer could be used on them to knock the wooden forms off, which would explain some of the nails left behind.) The weird "melting tool" often mentioned as being found was most likely just like the ones they use now to vibrate the air out of poured concrete.
It wouldn't surprise me if some of the really large stones were hollow as well. In fact, I don't think that most of them are as heavy as is claimed.
Could that be how he did it? (IMO, yes. Hate me if you must....
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Does that take away from the wonder that he built?
No, of course not....
