The territory of Casale Marittimo is rich of archaeological finds testifying its ancient origins, like the Etruscan necropolis and other sepulchres equipped by fine funerary dowries dating back to the same time so that testifying the presence of this rich civilization in the territory, who settled down in Casale Marittimo for its richness of water springs and minerals.

Very interesting is also the ancient Church entitled to Saint Andrew, recently restored and transformed so to host the Municipal offices of Casale Marittimo. The stone-made facade shows its original features and, on the main portal, a bass-relief made by Alberto Sparapani, portraying "Saint Andrew". The interior of the church shows a wooden roof covered by painted trusses and it rich of numerous frescoes painted by Stefano Ghezzani. Particularly interesting are also the Our Lady of the Graces Chapel and the Saint Sebastian Church. The first one was built in the XVIII-th century and it still saves today a copy of an original plate painted by some artist from Siena, whereas the Saint Sebastian Church was built on a pre-existing oratory and restored by using original materials coming from a Roman villa.

The Saint Sebastian Church still saves today a rare wooden sculpture by Giovanni Maria Tacci, dating back to the XVI-century and portraying a "Wounded Christ held by some Angels", whereas some of the finest art works belonging to the ancient building are saved today in the "Museum of Holy Art of Volterra", among them a painting portraying an "Our Lady with the Child between the Saints Sebastian and Rocco"