Casole d'Elsa houses a museum that intertwines the archaeological heritage with the historical-artistic one. The heart of the small town is the famous Collegiate Church alongside which, in the rectory, there are rooms dedicated to archaeological finds and works belonging to the territory of Casole d'Elsa. Of great interest are a marble statue head from the 19th-century collection of the Marquis Bargagli and two bronze buckles depicting a boxing scene which attest to the economic and cultural vitality of this area in the Archaic Etruscan age. The numerous grave goods of the Hellenistic age, found in the necropolis of Orli, instead prove Casole's belonging to the political-cultural sphere of Volterra.

The historical-artistic section of the Archaeological Civic Museum and the Collegiate Church of Casole d'Elsa consists of two important groups of works carried out by the painters Alessandro Casolani (1552 / 1553-1607) and Augusto Bastianini (1875 - 1938) born respectively in Mensano and Monteguidi, two castles in the Casole countryside. The museum also houses some late medieval and Renaissance works, including a fresco by Giacomo Pacchiarotti attesting to the success of the Umbrian school of Pinturicchio in Siena in the early sixteenth century. The tour ends in the monumental Collegiate Church of Santa Maria Assunta in which among the numerous works stand out two great fourteenth-century funeral monuments: the cenotaph of Messer Porrina made by Marco Romano and the sepulcher of Bishop Tommaso Andrei sculpted by Gano di Fazio, an altarpiece by Giovanni della Robbia and a painting by Rutilio Manetti from Siena.