The museum is housed in the rooms of the Benedictine convent of S. Matteo in Soarta (11th cent) very little of which remains after alterations and restoration after the last war, apart from the church and a few pieces of medieval wall.
The late medieval cloisters were built in brick with double mullions and columns and capitals, almost all of which are original, on the upper floor. The colonnade was largely restructured in the 16th cent., together with other parts closed to the public. In the early 19th cent. a Chapter of Canonesses was installed and the neoclassical entry was built at this time. Between 1866 and 1940 it became the town remand home, which required much structural adaptation.