The splendid complex of Saint Galgano is at around 20 minutes / half an hour drive from Siena, located west, between Monticiano and Chiusdino, in a wild territory, with wonderful landscapes and natural panoramas.
The Abbey of Saint Galgano has represented throughout the centuries an important stop for travelers and pilgrims in the Merse Valley, which was a densely populated territory, rich in churches, castles, villages and monasteries and that included the municipalities of Monticiano, Chiusdino, Murlo and Sovicille.
Two roads of great historical and economic importance pass here, the Massetana road, connecting Siena with the Sea and crossing Massa Marittima (very important town of the Past) and the Metalliferous Hills and the ancient Maremmana Road joining the center of Tuscany with Grosseto.
I really suggest you to visit the Abbey of San Galgano (Abbazia di San Galgano) and the Montesiepi Chapel (Eremo di Montesiepi) next to it and then to drive forward Massa Marittima passing through Montieri, in a really unspoilt and interesting territory!!
For the history of this magical places, please visit the following website, which I find rich in contents and well written:
San Galgano Abbey