The basilica is the result of the extensive rebuilding of an earlier basilica that had the apse to the east and the entrance to the west, through a wide tripartite narthex of which the dividing arches remain. Two rows of grey granite columns divided it into three naves. In the mid-6th century AD, a new apse was created in the narthex of the phase I basilica. The main entrance to the basilica in the 2nd phase was via a flight of steps leading into a kind of vestibule paved in mosaic. The nave had an opus sectile floor in the presbytery and a mosaic floor in the remaining eastern part.