The Castle of Marmilla is a military fortress dating back to the times of the Giudicato, whose ruins rise in the territory of Las Plassas atop a hill that is 270m in height, perfectly conical and with a rounded shape, from which derives the name of Marmilla (as in ‘mammillary’), a rich ‘land of wheat’.
The castle was mentioned for the first time in a document dating back to 1172, the year in which it was ceded by the Giudicato of Arborea to the Republic of Genoa. Its origins date back even earlier, within the first half of the 12th century. It was the protagonist of the Middle Ages on the island, marked by protracted disputes. Following sa Batalla di Sanluri (the Battle of Sanluri in 1409), it became part of the Aragonese dominions, maintaining its defensive function for a century. Some rooms of the Castle, still in use during the feudal age, were then utilised as a prison until the 19th century.
The fortress, built on a rocky base ‘levelled out’ with blocks of squared sandstone, has an irregular hexagonal format, utilising all of the space at the top of the hill (550 square metres). It has undergone several renovations, the most significant operation dating back to Giudice Mariano II (late 13th century).
In 2001, it was the subject of a consolidation project. To be admired today is the almost-intact main tower and walls, both perimetric and internal, and a large cistern dug into the rock, which together with one beyond the wall, ensured the supply of water. There is also a marked articulation of the rooms - garrison quarters, warehouses, grain stores, arms courtyard and guard area.
During the excavations, parts of the architectural furnishings, ceramics of fine workmanship (from the 13th to 16th century), the remains of a millstone, fragments of weapons, glass and food were found. These finds are exhibited in the museum of Castello MudA, housed in a 19th-century Campidanese residence in Las Plassas.