Montevarchi was developed as a “mercatale” – market place- along the main road which connected Arezzo to Florence, at the foot of the castle which initially belonged to the Marquis of Pierle and then to Count Guidi. Montevarchi passed under the jurisdiction of Florence in 1273 and became such an important border town and trade centre that it became necessary to build strong and effective defences.
The town walls were built by the Florentines in 1328 and developed following the elliptical shape of the town The two main gates were part of the structure and were at either end of what is today Via Roma (Porta Fiorentina e Porta Aretina), there were other five minor gates, a rampart which protected the market area and two towers the most imposing of which was il Cassero, still visible today. .
Il Cassero had an active military functon and was made up of a “tower to which was attached the gatehouse for the soldiers who would come down from the tower and rest once they had finished their guard duty..” (Conti, 1770).
The change in political and economic dynamics which took place throughout the following centuries transformed Montevarchi from a military outpost to a manufacturing and agricultural town. However, the walls were kept and maintained until the17th Century when they fell into disuse and were partly destroyed or incorporated into new buildings.
At the end of the 18th Century il Cassero was sold to private owners but the structure was left unaltered. In the second half of the nineteenth century the building was bought by the Province of Arezzo and in the first decades of the twentieth century was restored and regained its original defensive function when it became the headquarters for the local Carabinieri. In 1996 the Provincial Administration of Arezzo granted the structure on loan to Montevarchi Council which decided to restore it. The restoration work was completed with the aim of turning the Cassero into a museum and archive.