The building is in Apulian Romanic style, which is one of the most mature artform in Apulia. On the outside, the facade, terminating in highlights, has the classic tripartition rendered by the presence of pilasters and further marked by the presence of three portals for each nave. The central one has an elaborate decoration with a double archivolt with different animals and plants, on the top of which stands a pelican. Below the upper circle two griffins support the weight of the structure resting on two slender columns equipped with a Corinthian capital, which in turn have as a base two lions, an element the latter typical of the entrances of the period at the turn of the eleventh and twelfth centuries. Noteworthy for the rarity of the scene is the bas-relief carved on the lintel where we find represented three scenes: the Annunciation, the Visitation, the Epiphany and the presentation in the Temple of Jesus. Remarkable is also the representation of an 'anastasis' in the central lunette. The rose window on the sixteen-arm facade also has on top one of the classic images of the period: a sphinx. The long side of the church overlooking the square sees the presence of a porch made of hexaphores resting each on a deep arch, like those of the Basilica of San Nicola di Bari. Pope Gregory IX excommunicated Emperor Frederick II. The interior, a Latin cross, has three naves with supports of two columns and a pillar, another typical element of Romanesque, along with the wooden trusses of the central nave. On the southern ones there are instead the matronei. Between the elements of the decoration we find an ambo and the ciborium of Gualtiero di Foggia. Below the transept is the crypt that allows access to the early Christian basilica of the fifth-sixth century. The visit route allows you to see, in addition to the floor mosaics, wall frescoes that were buried to build the complex of medieval times. This operation has allowed to preserve a mosaic of the year 1000, perfectly preserved, realized in opus sectile, and that represents a griffin symbol of the double nature of Christ, human and divine.

The cathedral of Bitonto is dedicated to San Valentino. It was built between the end of 1000 and the 1100. A certain date is the attesting of the bishopric since 1089 when it is mentioned in Bishop Arnulf’s sources. Archeological excavations were conducted in 1991 behind the naves and through these the previous paleochristian basilica, dated between fifth and sixth century, was discovered.