The village grew up over the centuries in what was once the suburbs of Ostia proper. Its history is irrevocably linked to the growth of Christianity and it immediately gained the status of diocese after the Emperor Constantino declared freedom of worship in 313 AD. From the 4th century AD onwards the bishop of Ostia has traditionally crowned the newly elected pope. Written fragments seem to indicate Ostia Antica as the burial place of the young martyr St. Aurea, who died in 258 AD under the reign of the Emperor Claudius the Goth. Ostia Antica's cathedral, rebuilt on the ruins of an earlier church, is dedicated to the saint.
During the 9th century AD Pope Gregory IV sheltered the remaining local population in the village which he fortified against the raids of marauding Arab pirates. In the 15th century AD Martin V, the Colonna Pope, built a massive moated tower on the banks of the Tiber as part of the defense of Rome, today the tower is part of the castle. In 1472 Pope Sisto IV, charged the rebuilding of the village. The project was completed in 1479 giving the village houses as we can still see them today and the village fountain, made from an authentic Roman sarcophagus.

In 1483 Giuliano della Rovere became Bishop of Ostia and acts was to initiate a further massive rebuilding. The moat was widened, although in fact it was only flooded when necessary, a further check to troops assaulting the gate was the erection of a defensive redoubt facing the village and thus out of enemy cannon shot. The castle is an irregular triangular shape to fit the course of the river, the whole is dominated by an enormous keep 24 meters high and 15 meters wide in order to encompass Martin V's original tower.
Two episodes marked the decline of the castle during the 16th century; it was besieged by the Duke of Alba in 1556 and the year after the Tiber burst its banks, shifting its course permanently 2 km to the north of Ostia Antica.

For information visitors to the Castle should call: 56358013.
Open 9:00 to 13:00.
Tuesdays and thursdays 14:30 - 16:30.
Closed mondays.

Lipu Ostia