The San Galgano abbey rises in the Merse river valley, between the medieval boroughs of Chiusdino and Monticiano, in the Siena province. The Cistercense abbey ruins of San Galgano emerge greatly with the sun shining on the vast countryside. The imposing building, which exerts a fascination impossible to describe, remains only an external structure. The church, by now completely without a top, has the stars as its roof. Suggestively, in the springtime, the floor of the church is blanketed in daisies. Today, because of its strange beauty, it is even home to classical music concerts.

The abbey gets its name from Guidotti Galgano, a noble horseman, first a hermit then a saint, originally from Chiusdino, were he was born in 1148. From San Galgano comes the story of the sword in the stone. It is told that Galgano put his sword in the rock to symbolize the cross. "The sword in the Stone" can still be seen inside the Montesiepi church which rises next to the San Galgano abbey. Incredibly elegant, the dome of the church is made up of alternating rows of red and white stone. It is also home to the roman tombs of Ceveteri and Vetulonia.