Portus
Portus was a large artificial harbour of Ancient Rome. Sited on the north bank of the north mouth of the Tiber, on the Tyrrhenian coast, it was established by Claudius and enlarged by Trajan to supplement the nearby port of Ostia.[1]
The archaeological remains of the harbour are near the modern-day Italian village of Porto within the Comune of Fiumicino,[2] just south of Rome in Lazio (ancient Latium).
Rome's original harbour was Ostia. Claudius constructed the first harbour on the Portus site, 4 km (2+1⁄2 mi) north of Ostia, enclosing an area of 250 hectares (617 acres), with two long curving moles projecting into the sea, and an artificial island, bearing a lighthouse, in the centre of the space between them. The foundation of this lighthouse was provided by filling one of the massive obelisk ships, used to transport an obelisk from Egypt to adorn the spina of Vatican Circus, built during the reign of Caligula. The harbour opened directly to the sea on the northwest and communicated with the Tiber by a channel on the southeast.
The goal was to obtain protection from the prevalent southwest wind, to which the river mouth was exposed. Though Claudius, in the inscription which he erected in AD 46, stated that he had freed the city of Rome from the danger of inundation, his work was only partially successful: in AD 62 Tacitus speaks of a number of grain ships sinking within the harbour during a violent storm. Nero gave the harbour the name of "Portus Augusti".[1]
It was probably Claudius who constructed the new direct road from Rome to Portus, the Via Portuensis, which was 24 km (15 mi) long. The Via Portuensis ran over the hills as far as the modern Ponte Galeria, and then straight across the plain. An older road, the Via Campana, ran along the foot of the hills, following the right bank of the Tiber. It passed the grove of the Arval Brothers at the sixth mile, to the Campus salinarum romanarum, the saltmarsh on the right bank from which it derived its name.[3]
In AD 103 Trajan constructed another harbour farther inland—a hexagonal basin enclosing an area of 39 hectares (97 acres). It communicated by canals with the harbour of Claudius, with the Tiber directly, and with the sea, the last now forming the navigable arm of the Tiber, reopened for traffic by Gregory XIII and again by Paul V. The new canal bore the name Fossa trajana, though its origin is undoubtedly due to Claudius. The basin itself is still preserved, and is now a reedy lagoon. It was surrounded by extensive warehouses, remains of which may still be seen: the fineness of the brickwork of which they are built is remarkable.[1]
