Early Ostia

To the east of Ostia were salt-pans, where salt was probably already extracted in the Middle and Late Bronze Age (1400-1000 BC). There may have been a small village near the salt-pans in the Early Iron Age (1000-700 BC). Livius mentions Ostia twice in his accounts of the fifth century (and exceptional floods of the Tiber in 414 and 363 BC). However, according to ancient tradition (authors such as Ennius, Livius, Cicero and Dionysius of Halicarnassus) Ostia was founded as a colony of Rome earlier, by the fourth king of Rome, Ancus Marcius, who was thought to have ruled in the late seventh century BC. Even the year is mentioned: 620 BC. So far no remains of buildings have been found in or near Ostia dating from this period. If a settlement existed, then it must have been a small outpost, not even a village.

Fragments of an inscription from the Imperial period. A[nco] MAR[cio] REG[i Rom(ano)] QVART[o a R]OMVL[o] QVI AB VR[be c]ONDIT[a] [pri]MVM COLON[iam] [c(ivium) rom(anorum)] DEDUX[it] To Ancus Marcius, fourth king of Rome from Romulus, who after the founding of the City first of all founded the colony of the Roman citizens. The Ostians, like many ancient authors, claimed that the city was founded as a colony by king Ancus Marcius.

The oldest settlement that has been found is the so-called Castrum. It was a rectangular military fortress (194 x 125.7 meters), with walls of very large tufa blocks. The current Forum is in the centre, and a few remains of the Castrum walls can still be seen around the Forum. The two main streets, leading to four gates, were called Cardo and Decumanus. These would create regularity in the street pattern of Ostia when the city grew. However, there is also a great irregularity in the lay-out of parts of Imperial Ostia. This must be the result of a very old road, perhaps from the sixth or fifth century BC, that started at the mouth of the Tiber and continued towards the south-east.

Remains of the Castrum wall. Photo: Daniel González Acuña.

From some historical events can be deduced that the Castrum was built in the fourth or early third century BC. Most modern historians have suggested that it was erected in either 349/8 or 338 BC, a period when Rome had to battle pirates and was at war with its neighbours. The oldest pottery found in the Castrum has been dated to the period 380-340 BC. More recently other proposals have been made: the late fifth century BC, in view of the origin of the tufa blocks (from Fidenae); the year 311 BC, because two duumviri navales, officials in charge of ships, were appointed (but they may also have been active in the harbour district in Rome itself); 300-275 BC, because pottery found next to the foundation of the walls belongs to that period (with the suggestion that the older pottery could be the remains of votive offerings from an older temple, curiously isolated however). According to the most convincing hypothesis the Castrum belongs to the period 292/1 BC (when the god Aesculapius was taken to Rome, but Ostia is not mentioned) to 278 BC (when a Carthaginian fleet is said to have reached Ostia).