Cella trichora, a trefoil-shaped memorial chapel, with an elliptical vestibule in the front. It used to be a freestanding building, separate from the church. While it probably served as a memorial building for venerating a saint’s relics, it may also have been built as a mausoleum-tomb for a privileged person. In its impressive vaulted room, important remains of the original floor mosaic from the 6th century have been preserved. In the centre, there is the marble sarcophagus of St. Maurus and St. Eleutherius, built at the time of Bishop Paganus. The sarcophagus hosted the relics of St. Maurus and St. Eleutherius until 1354 when, during the war between Venice and Genoa, the church was looted and the bodies of the Parentine saints were taken to Genoa, whence they returned only in 1934. At the side bottom of the sarcophagus, an attentive observer will notice two pairs of five small holes. Those were the openings that enabled the circulation of “power” that emanated from the relics.