The Sator Magic Square in Turin. The formula was widely diffused throughout the city in the Medieval period among the members of the Templar Order.
It's a word square containing a Latin palindrome featuring the words SATOR AREPO TENET OPERA ROTAS written so that they may be read top-to-bottom, bottom-to-top, left-to-right, and right-to-left.
One of its meanings may be: "The sower Arepo leads with his hand (work) the plough (wheels)."
More information: Wikipedia here
Informazioni sul Quadrato del Sator: Wikipedia qui
