right St. Peter gives the stole to Leo III and the standard to Charlemagne, an image meant to represent the Frankish king's duty to protect the Church. The second triclinium built by Leo III, also known as the Aula Concilii ("Hall of the Council" or Sala del Concilio in Italian), was situated next to the basilica and in perpendicularly to it. It was a magnificent oblong hall (53 m long by 13 wide) with eleven apses, the major apse on one end and five on each side. The side apses had a diameter of 6.7 meters and were 2.34 meters apart, while the end ones were 4.47 meters away from the front and end walls. A large Porphyry fountain was placed in front of the main apse, spouting jets of water from pressurized pipes of the restored Aqua Claudia, a technical marvel meant to impress visitors. Each of the 10 lateral apses held accubita for banquets, on the model of the reception hall of the 19 accubita in the Great Palace of Constantinople. The main apse was decorated with a mosaic showing Christ and Mary with Saints Peter and Paul and three other figures, while each of the ten lateral apses was decorated with frescoes depicting an apostle preaching to the gentiles. On the left of the main apse was a staircase that lead to the basilica. The hall was adorned with columns, pilasters, a floor in opus sectile. A drawing by Pompeo Ugonio (BAV, Cod. Barb. lat. 2160, fol.157v) survives as evidence of its structure and ornamentation. Leo III and his successor Paschal I (817–24) decorated the Sancta Sanctorum (“Holy of Holies”, the private papal chapel) with new jeweled reliquaries and a reliquary chest modeled on the Ark of the Covenant, which stored some of Rome’s most precious relics. Around the 820s the Liber Pontificalis starts calling the complex a palace, palatium. The private apartments of the popes in this palace were situated between the triclinium and the city walls. It later was called Aula Concilii ("Hall of the Council") due to its role as a place of meetings. In the tenth century Sergius III restored the palace after a disastrous fire, and later it was greatly embellished by Innocent III. This was the period of its greatest magnificence, when Dante speaks of it as beyond all human achievements. At this time the centre of the piazza was occupied