- For homonyms, see Porto (disambiguation)
Porto (Italian) or Portus (Latin) was a town in Lazio or Latium, just south of Rome, Italy. It was an ancient harbour on the right bank of the mouth of the Tiber.
Rome's original harbour was Ostia
constructed the first harbour on the Portus site, 4 km (2.5 miles) 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 a massive ship, used to transport a obelisk
from Egypt to adorn the spina
of Vatican Circus
, build under Caligula
the harbor thus opened directly to the sea on the north-west and communicated with the Tiber by a channel on the south-east. The object was to obtain protection from the prevalent south-west wind, to which the river mouth was exposed. Though Claudius, in the inscription which he caused to be erected in A.D. 46, boasted that he had freed the city of Rome
from the danger of inundation, his work was only partially successful. For in the 62 AD Tacitus
speaks of a number of grain ships sinking within the harbor during a violent storm. Nero
gave the harbor the name of "Portus Augusti".
It was probably Claudius who constructed the new direct road from Rome to Portus, the Via Portuensis which was 24 km (15 miles) 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, and passing the grove of the Arval Brothers at the sixth mile, to the Campus salinarum romanarum, the saltmarsh on the right bank from which indeed it derived its name.
In 103 AD Trajan
constructed another harbour farther inland—a hexagonal basin enclosing an area of 39 hectares (97 acres), and communicating by canals with the harbour of Claudius, with the Tiber direct, 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
). It 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.
Farther to the east is a circular building in brick with niches; it is called the temple of Portumnus. To the east again is the so-called Arco di Nostra Donna, a gateway (possibly originally built by Trajan) in the Constantinian fortifications around the port.
Effects on Ostia
By means of these works Portus captured the main share of the harbour traffic of Rome, and though the importance of Ostia did not at once decrease we find Portus already an episcopal see
in Constantine's time not very long (if at all) after Ostia, and as the only harbour in the time of the Gothic wars.
Its abandonment dates from the partial silting up of the right arm of the Tiber in the middle ages, which restored to Ostia what little traffic was left. To the west of the harbour is the cathedral of S. Rufina (10th century, but modernized except for the campanile) and the episcopal palace, fortified in the middle ages, and containing a number of ancient inscriptions from the site. On the island (Isola Sacra) just opposite is the church of S. Ippolito, built on the site of a Roman building, with a picturesque medieval campanile (13th century ?), as well as the Isola Sacra Necropolis; 3.2 km (2 miles) to the west is the modern village of Fiumicino at the mouth of the right arm of the Tiber, which is 34 km (21 miles) west south-west by rail from Rome. It is a frazione, or portion of the commune of Rome. 5 km (3 miles) to the north is the pumping station by which the lowland (formerly called Stagno di Maccarese, now reclaimed and traversed by many drainage canals) between there and Maccarese is kept drained (Bonifica di Maccarese).
The site can still be fairly clearly traced in the low ground to the east of Fiumicino
, and the lighthouse is represented in bas-reliefs. The harbour is generally supposed to have been protected by two moles with a breakwater in front, on which stood the lighthouse, with an entrance on each side of it. Trial soundings made in 1907 showed that the course of the right-hand mole is represented by a low sandhill, while the central breakwater was only some 170 m long, and probably divided from each of the two moles by a channel some 135 m wide. The existence of two entrances is, indeed, in accordance with the evidence of coins and literary tradition, though the position of that on the left is not certain, and it may have been closed in later times. The whole course of the left-hand mole has not yet been traced, but it seems to have protected not only the south-west but also a considerable portion of the north-west side of the harbour.
Many other remains of buildings exist; they were more easily traceable in the 16th century when Pirro Ligorio and Antonio Labacco made plans of the harbour. Considerable excavations were carried on in 1868, but unfortunately with the idea of recovering works of art and antiquities; and the plan and description given by R. Lanciani (Annali del institute, 1868, 144 sqq.) were made under unfavourable circumstances.
Medieval and modern town
The division between the ancient settlement and the medieval Porto began in the 4th century CE, when emperor Constantine the Great
had a line of walls built.
Ostia, just opposite, on the left bank of the Tiber, was increasingly depopulated after Vandal and Saracen attacks.
Porto was the main port on the Tyrrhenian Sea until the 6th century CE. Later it decayed, but maintained some importance as the episcopal see of a bishop which, from 313, was made independent from that in Ostia. Ostia and Porto both were chosen to be amongst the seven suburbicarian dioceses, which are still in existence, and reserved for the members of the highest order of Catholic Cardinals, the Cardinal Bishops, so the prelates of these otherwise insignficant Roman suburbs outrank all archbishops, even the patriarchs.
The remains of Porto are today included administratively in the frazione of Ostia of the comune of Rome.
- Rendina, Claudio (2000). Enciclopedia di Roma. Rome: Newton Compton.
- Westermann, Großer Atlas zur Weltgeschichte