The church is a perfect illustration of the Sardinian Romanesque and the most important monument in Olbia. It was built in three stages between the late 11C and early 12C. On the sober façade, in the arch to the left of the portal, a marble bas-relief and eight niches for ceramics can be made out. Inside, the three naves are separated by arcades supported by the columns and pilasters of rubble-stones. The decoration on the capitals is quite basic as granite is a difficult material to sculpt.