My Guess. Old World Concrete
(media.conspiracies.win)
You're viewing a single comment thread. View all comments, or full comment thread.
Comments (58)
sorted by:
It's not just that the stone was placed there? It's also been machined almost perfectly flat. I think the obvious answer is, they had technology back then which we assumed didn't exist.
We still don't have vertical vibra-screeds today. ;(