Cagliari's cathedral occupies the highest point of the Castello quarter, a white Baroque facade (17th century) attached to a Romanesque-Pisan interior of the 13th century. The mixture of periods reflects the building's long history of modification, but the result has real character. The two Romanesque pulpits, donated by Pisa in 1312, are among the finest examples of pre-Pisano carving in Italy and alone make the cathedral worth visiting.
In the crypt below the nave, which was carved out of the rock in the 17th century, over six hundred niches hold the bones of early Christian martyrs transferred from the church of San Saturnino. The crypt is a strange, slightly unsettling space, its walls lined with inscribed marble panels. Upstairs, the treasury contains the silver votive offerings presented by devotees over several centuries — an accumulation of beliefs and gratitude rendered in metal.