The Porta San Paolo is one of the southern gates in the 3rd-century Aurelian Walls of Rome. The Via Ostiense Museum is housed within the gatehouse.
The original name of the gate was Porta Ostiensis, because it was located of the beginning of via Ostiense, the road that connected Rome and Ostia where functioned as its main gate. Via Ostiense was an important arterial road, as evidenced by the fact that upon entering the gate of the same name, the road split, with one direction leading to the famous Emporium, the great market of Rome.
The gatehouse is flanked by two cylindrical towers, and has two entrances, which had been covered by a second, single-opening gate, built in front of the first by the Byzantine general Belisarius (530s–540s).
The structure is due to Maxentius, in the 4th century, but the two towers were heightened by Honorius. Its original — Latin — name was Porta Ostiensis, since it opened on the way to Ostia. Later, it was renamed to the Italian Porta San Paolo, because it was the exit of Rome that led to the Basilica of St. Paul Outside the Walls.
In 549, Rome was under siege; the Ostrogoths of Totila entered through this gate, because of the treason of the Isaurian garrison. On 10 September 1943, two days after the armistice between the Allies and Italy had been agreed, Italian military and civil forces tried to block German seizure of the city, with 570 casualties.
References:Rosenborg Palace was built in the period 1606-34 as Christian IV’s summerhouse just outside the ramparts of Copenhagen. Christian IV was very fond of the palace and often stayed at the castle when he resided in Copenhagen, and it was here that he died in 1648. After his death, the palace passed to his son King Frederik III, who together with his queen, Sophie Amalie, carried out several types of modernisation.
The last king who used the place as a residence was Frederik IV, and around 1720, Rosenborg was abandoned in favor of Frederiksborg Palace.Through the 1700s, considerable art treasures were collected at Rosenborg Castle, among other things items from the estates of deceased royalty and from Christiansborg after the fire there in 1794.
Soon the idea of a museum arose, and that was realised in 1833, which is The Royal Danish Collection’s official year of establishment.