In the heart of the historic center of Bovino stands sober and imposing the Cathedral. In Romanesque style, with clear elements Byzantines, has the facade attributed to a gallic architect called Zano, who built it in 1231 on commission of the Bishop Peter I. The main entrance is delimited by two uprights that support the two shelves with floral motifs sculptured in the calcareous stone, and by a large archivolt ogival with frame decorated with palmette continue, which you set on two brackets with floral elements and zoomorphic figures. Also the portal on the right is surmounted by a pointed arch with a frame to leaves carved in stone. The roof that overhangs the aisles, lower than the central one, is asymmetric. In the top part, an ox, from the horns mozzate, dominates the entire facade. The interior has a Latin cross with the central nave double on the side naves and with raised presbytery from steps. The columns, all in granite, probably come from Roman buildings. They have different height, to which it is performed with the use of bases of size and different invoice (capitals pulvinar and Romans reused). Previous to the romanesque church are a baptismal font, formed by a big roman mortarium in stone on a ionic capital upside down and the columns that describe the arch of the apse with the shelves frescoed. The basilica closes, as usual, with an apse. The upper part of the wall is completely covered by the pipes of the organ. A staircase, open on the transept of the basilica, allows the direct access to the so-called "Cappellone" of San Marco. The church, originally autonomous, also presents a monumental portal, which gives on the outside, with a lunette reproducing in bas-relief S. Marco Aecae with mitre and pastoral, between two deacons who govern the liturgical furnishings. The building was constructed in 1197, as attested by an epigraph dated to 1703, perhaps on the occasion of the arrival in the city of the relics of the Saint, which then venerated as the Patron Saint of the country. This church has also covered the role of "cemetery of Bishops", for having hosted the monumental tombs of some of the most important bishops, that keep the ancient diocese of Bovino.