Portus

Portus

The mouth of the Tiber, with the hexagonal harbour of Portus at upper middle (modern day "Lago Traiano").
Shown within Lazio
Region	Lazio
Type	Settlement, Port
History
Periods	Roman Republic Roman Empire
Cultures	Ancient Rome
Site notes
Excavation dates	yes
Archaeologists	Guido Calza; Simon Keay
Public access	no

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.

The archaeological remains of the harbour are near the modern-day Italian village of Porto within the Comune of Fiumicino, 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 (2.5 mi) north of Ostia, enclosing an area of 69 hectares (170 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 thus opened directly to the sea on the northwest and communicated with the Tiber by a channel on the southeast.

The object was to obtain protection from the prevalent southwest wind, to which the river mouth was exposed. Though Claudius, in the inscription which he caused to be erected in AD 46, boasted 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".