Known as the "sword in the stone," the Tuscan "Excalibur" is said to have been plunged into a rock in 1180 by Galgano Guidotti, a medieval knight who renounced war and worldly goods to become a hermit.

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Galgano was thrown by his horse while passing Montesiepi, a hill near Chiusdino. There, another vision told him to renounce material things. Galgano objected that it would be as difficult as splitting a rock with a sword. To prove his point, he struck a stone with his sword. Instead of breaking, the sword slid like butter into the rock. Galgano once again became a recluse, isolating himself by the sword's side. There he remained until he died in 1181.

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If the sword really dates to 1180, decades before the first literary reference to the "sword in the stone," it would support the theory that the Celtic myth of King Arthur and his sword Excalibur developed in Italy after the death of Galgano.