The municipal Palace is made up by three contiguous buildings, dating back to different historical periods. The oldest part is the Bargello Tower, on the right side, built at the beginning of the XIII century; later the counts of Biserno gave the Municipality the part of their Palace we can now see at the left of the Municipal building.
The two towers were then connected to the Sienese Gothic styled central body during the XIV century. At the centre of the façade we can see a Mediceous coat of arms carved by Francesco Moschini in 1563, while in the Bargello Tower wall there’s a bas-reliefed she-wolf, as a symbol of the Sienese Republic and of the consequent loss of independence of the Municipality of Massa Marittima. It’s told that on the lower part of the Tower the town’s betrayers faces used to be painted.