Bosa, Serravalle Castle

Bosa, Castello di Serravalle o Fortezza Malaspina. Foto di Elisabetta Loi, da Sardegna DL

The town of Bosa stretches along the banks of the Temo river, climbing with the houses along the slope of the hill at the top of which the castle of Serravalle was built. The original nucleus of the city was always located along the Temo, but further inland, on the site of the church of San Pietro extra Muros.
The current town of Bosa, with the palaces and churches in the historic center, the castle and the former Romanesque cathedral of San Pietro Extra Muros, the ancient tanneries along the Temo, is one of the river places with the greatest tourist attraction in Sardinia, rich in historical and artistic emergencies.
Its historic center corresponds to Bosa 'nova', refounded on the banks of the Temo river near the river port. Just starting from the river, the village expands to the slopes of the hill, where the district of Sa Costa is located, at the top of which the castle of Serravalle was built. Near the cathedral of San Pietro, on the opposite bank of the Temo, is the nucleus of Bosa “vetus”, the original center of the town of Bosa.
At 81 meters above sea level stands the castle of Serravalle. Commonly called the Malaspina castle, it owes this appellation to the tradition that it was built in 1112 by the homonymous family of Tuscan nobles transplanted to the island in the mid-eleventh century.
The entire complex of the castle of Serravalle occupies one hectare, within which the actual castle, with a width of 2000 square meters, is located.
The fortification is still the subject of archaeological studies and excavations to clearly redefine its chronology and interventions. It is customary to identify three distinct chronological phases starting from the first plant, perhaps in the 12th century, to which parts of the wall to the north, including a tower, would belong. At the beginning of the 14th century, the tower N/E was rebuilt, typologically similar to the towers of the Elephant and of San Pancrazio, in Cagliari, built between 1305 and 1307. The tower is made of clear vulcanite, free of blackbirds, but ends in a series of protruding shelves. It was divided into three floors. Subsequently, the great wall was built, which includes seven towers of different shapes, a fence that, in addition to defending the actual castle, also encloses the church of Our Lady of Sos Regnos Altos.
Recent excavations would revolutionize the chronology of the site, ascribing the construction of the structures visible today after the Arborense conquest. However, it is necessary to wait for the completion of these studies to review the history of the castle of Bosa, a complex monument not only because of the stratifications inside it, but also because of the historical events that characterized it.

History of studies
Studies on the castle of Bosa and its settlement are numerous, given the importance of the site in the history of island art. See the text by Mario Pintor entitled “Bosa and his castle” (1963), the monograph edited by Salvatorangelo Spanu entitled “The Castle of Bosa” (1981), as well as the part relating to this fortification included in Foiso Fois's volume “Castles of Medieval Sardinia” (1992); in 1993 it is the summary sheet in Roberto Coroneo's volume “Romanesque Architecture from the mid-thousand to the first '300".

Bibliography
V. Angius, "Bosa (nuova)", in G. Casalis, Dizionario geografico storico-statistico-commerciale degli Stati di S.M. il Re di Sardegna, II, Torino, G. Maspero, 1834, pp. 526-541;
R. Carta Raspi, Castelli medioevali di Sardegna, Cagliari, 1933, pp. 115-121;
M. Pintor, Bosa e il suo castello, Cagliari, 1963;
Il castello di Bosa, a cura di S. Spanu, Torino, 1981;
F. Fois, Castelli della Sardegna medioevale, a cura di B. Fois, Cinisello Balsamo, Amilcare Pizzi, 1992, pp. 285-292;
R. Coroneo, Architettura romanica dalla metà del Mille al primo '300, Nuoro, Ilisso, 1993, scheda 179;
G. Serreli, Tutti i castelli dei quattro regni, "Darwin. Quaderni", n. 1 (luglio-agosto 2006), pp. 104-109.