In 1198, during the reconstruction of the church by the Benedictines, a tall campanile was added next to the top left hand corner of the atrium. This tower consists of seven storeys in brick separated by projecting cornices. The brick fabric of the campanile is embellished by plaques of purple porphyry and green serpentine, and at the top is a molded cornice with dentillations. There is a tiled pyramidal cap.