The museum collects numerous works of art, such as bas-reliefs, paintings on wood and canvas, reliquaries and sacred jewelry objects from churches in the area. Inaugurated in 2015 inside a historic building in the center of Chiusdino, the St. Galgano Civic and Diocesan Museum of Sacred Art is located a few kilometers from the evocative Abbey.
The works of particular significance include a splendid Madonna and Child by Niccolò Segna from 1336 from the Hermitage of Montesiepi, along with a number of works depicting St. Galgano such as the bas-relief depicting St. Galgano thrusting his sword into the stone by Urbano da Cortona from 1446, and Giovanni di Agostino's bas-relief of St. Galgano being led to Montesiepi, from the first half of the 14th century.
An important part of the museum is devoted to the life and figure of St. Galgano, a knight and hermit who was born in Chiusdino itself around the middle of the 12th century; the collection also includes the reliquary of the Holy head of St. Galgano.