The museum of Casole d’Elsa houses a collection that interweaves archaeological and artistic history.  At the heart of the town centre stands the well-known Collegiata (Collegiate church).  In the rectory next-door to the church, there are rooms dedicated to archaeological finds and to works of art from the territory of Casole d’Elsa. The head of a marble statue from the 19th-centurty collection of the Marquis Bargagli is of particular interest, as are two Etruscan buckles in bronze depicting a boxing match—amazing exemplars that demonstrate the economic and cultural vitality of this area during the Archaic Etruscan Period. Numerous funerary artifacts from the Hellenistic Period, unearthed at the Necropolis of Orli, prove instead that Casole belonged to the political and cultural sphere of Volterra.

The historical and artistic section of the museum is made up of two important collections of works by the painters Alessandro Casolani (1552/1553-1607) and Augusto Bastianini (1875-1938) who were born respectively in Mensano and Monteguidi, two castles in the countryside near Casole. The museum also houses late-Medieval and Renaissance works, including a fresco by Giacomo Pacchiarotti which shows the good fortune that the Umbrian school of Pinturicchio enjoyed in Siena during the early 1500s. The museum itinerary concludes in the monumental Collegiata di Santa Maria Assunta (Collegiate Church of Saint Mary of the Assumption).  Noteworthy among the numerous works of art here are two large burial monuments from the 1300s:  the Cenotaph of Messer Porrina, made by Marco Romano, and the tomb of the bishop Tommaso Andrei, sculpted by Gano di Fazio.  No less interesting is the altarpiece by Giovanni della Robbia, or the painting by the Caravaggio-style Sienese artist Rutilio Manetti.