Excavations revealed that this Carolingian cathedral had three naves and three apses. These churches had three naves and three apses. It consists of three largely Romanesque naves with Gothic vaulting. The structure has 5 naves, 5 apses, and (quite surprisingly for Byzantine architecture) 13 cupolas. It consists of five naves with transept and double ambulatory. Inside are spiral staircases ascending to the clerestory and the vaults of the naves. Each of the two side naves contain seven chapels. Three out of the four sections of the naves and transepts were also built. The fourteen chapels in the east and west naves are listed below. The new structure, consisting of three naves and seven chapels, was blessed in 1614. It is divided into two naves with Gothic rib vaults. The central naves are flanked by seven smaller parallel naves. The seven naves parallel to the qibla wall includes seven bays. These buildings had long naves and small rectangular chancels; porticus sometimes surrounded the naves. The interior is divided into three naves.