As a five-year (2017-2021) project run by the École française de Rome entitled“Ostie-Portus, hub de l’empire romain”, the study of the north-south wharf at Portus came out of a wider programme researching the port of Claudius, undertaken through the study, just completed, of the so-called Magazzini Traianei di Portus.
Probably built as a direct continuation of the colonnade of the Portico of Claudius, which flanked the west side of this vast warehouse complex, the north-south wharf forms the back-bone of the port system built by Claudius, and forms the link with the later Trajanic reorganisation. One of this new study’s main objectives will be to find evidence of a construction connection between the Portico of Claudius and the wharf, which together must have created a majestic seaward facade, several hundred metres long, leading into the centre of the port system.
At present, the wharf structures are largely covered by vegetation. However, the entire length of the monument’s “donkey-back” outline is perceptible between the end of the Portico of Claudius, at the north-western corner of the so-called Magazzini Traianei, and the modern so-called Casaletto, situated 350 m further north, at the feet of the piers supporting the over head road (via dell’Aeroporto di Fiumicino) that are built on the wharf structures themselves.
The first investigations, begun in October 2017, looked at the terminal part of the wharf, around the Casaletto, with the opening of two trenches, which, in substance, were limited to cleaning the surface of almost 350 m2 of structures. The aim of this first campaign was to recognise the technical characteristics of the wharf construction, identifying possible differences in the construction phases. Topographical surveys were undertaken, which determined the exact position of the wharf’s structural remains within the ancient harbour basin and precisely positioned them in relation to the orientation of the large warehouse structure.

This campaign showed that in its original Claudian phase the wharf was smaller than foreseen and that the part investigated in 2017 corresponded with two later extensions to the wharf. A first extension, about 40-45 m long by 6 m wide dated to the Severan period. In a later phase, a new structure was built abutting the seaward side of the first extension, which doubled the width of the Severan wharf (total width 14 m) and extended the length for s further 60-65 m towards the north. The terminal part of the latter extension of foundations, still visible behind the Casaletto, was characterised by the reuse of large marble fragments in the foundations to consolidate this zone, which probably had to support a particularly large architectural structure, for example a monumental warning lantern.

The next campaign will be dedicated to the study of the original wharf, in particular the final section abutted by the two extensions. The other campaigns in the five-year programme will investigate the area of contact between the wharf and the Portico of Claudius, in which several structures associated with a small bath complex, probably of late date, are visible.