Bosa, Cathedral of the Immaculate Conception

The historic center of Bosa was formed in the 12th century, at the foot of the castle of Serravalle, in a different place from that of the Roman and early medieval city, where the former Romanesque cathedral of San Pietro extra Muros is located.
The cathedral is located on the most remote part of the long Temo, near the oldest access to the city that overcomes the obstacle of the river through a volcanic stone bridge. It can be accessed from Piazza Duomo or from Corso Vittorio Emanuele II.
The cathedral of Bosa, dedicated to the Immaculate Virgin, was rebuilt on a 12th century church, roughly at the same time as the construction of the Malaspina castle, which led to the urbanization of the south bank of the Temo river and the progressive abandonment of the area where the ancient Romanesque cathedral of San Pietro stands.
After repeated renovations (including a late Gothic one of which a trace remains in some sections of the wall), the current appearance dates back to the remodeling carried out starting in 1803, under the direction of the Bosano master builder Salvatore Are, assisted later by Ramelli from Sassari. The new building, expanded by the chapel of the Sacred Heart - which is accessed through a vaulted compartment that interrupts the main wall near the entrance compass - was solemnly consecrated in March 1809.
The interesting façade, penalized by the narrow opening overlooking it, reworks late Baroque motifs derived mostly from the “altarpiece” façade of the local Carmel church, with a division of the surfaces into two orders separated by a large overhanging ledge and the vertical scan marked by pilasters and sturdy pilasters, all in exposed red volcanite. The interior space has a single aisle with side chapels (three on the d. side and four on the upper side), with a lunetted barrel roof, which receives light from the large windows in line with the chapels. The four bays are underlined by pilasters with capitals, combined with the ledge that marks the entire insertion of the vaults.
The raised presbytery is dominated by a tall dome on an octagonal drum set on plumes, designed - always in the very early years of the nineteenth century - by the royal architect and ornatist Domenico Franco.
Between 1877 and 1878, it was decorated inside with tempera paintings by Emilio Scherer from Parma, depicting Dante's paradise. Behind the eighteenth-century marble altar, embellished with polychrome sculptures and carvings, there is an apse, of considerable depth, with a wooden choir. The intradosso and the basin are also enriched by paintings by Scherer, as are the side walls of the presbytery.
The chapel looks like an independent building, with side altars and a slightly raised and domed presbytery. Between this and the main body of the church there are several rooms including the Chapter Hall and the sacristy.
Next to the presbytery, but not aligned to this, stands the bell tower: a parallelepiped divided into three orders marked by frames and corner pilasters, the only completely surviving element, although never completed, of an intermediate phase of the construction events of the cathedral, clearly revealed by the date 1683 carved on the triangular timpanet of one of the four windows of the bell cell.

History of studies
The church is the subject of a brief summary in Salvatore Naitza's volume on late seventeenth-century and purist architecture (1992).

Bibliography by
A. Sari, “Notes on Ecclesiastical Architecture in Bosa and its Territory”, in The Churches of Bosa, Documentation Notebooks of the Pro Loco of Bosa, Cagliari, Seleni, 1978;
S. Naitza, Architecture from the Late 17th Century to Purist Classicism. Nuoro, Ilisso, 1992, sheet 60;
A.F. Spada, The Churches of Bosa, Sestu, Zonza, 2002.