New discovery at Portus, the ancient port of Rome, features in the Daily Telegraph

Archaeologists from the University of Southampton, University of Cambridge and the British School at Rome, have discovered one of the largest canals every built by the Romans. They believe it linked Portus with the nearby Roman river port of Ostia.

The image shows an aerial view from Portus across the Fossa Traiana towards the Isola Sacra with Ostia in the far distance, an area that was crossed by the newly discovered canal.

The Portus team have found what we think is one of the biggest canals ever built by the Romans. Our geophysics work has identified what appears to be a 90 metre-wide canal, running southwards across the Isola Sacra from the maritime port of Portus to the river port at Ostia. Our current hypothesis is that this may have enabled cargo to be transferred from big ocean-going ships to smaller river vessels at Portus, and then on via the canal to Ostia for handling at the river port. Such a canal would have replaced the supposed overland route along the Via Flavia. Our latest work provides a new and important contribution to understanding the broader relationship of Portus to both Ostia and Rome.

We know of other, contemporary canals at the port which were 20-40 metres wide, and even those were big. But this is wider than anything we have found to date at Portus. It was so big that there seems to have been an island in the middle of it, and there was a bridge that crossed it. This new information further develops our understanding of the extraordinary trading network that the Romans developed throughout the Mediterranean basin, from Spain to Egypt and Asia Minor. Our work at Portus is also providing compelling evidence that trading links with North Africa in particular were much more extensive than previously believed. We have found hundreds of amphorae which were used to transport oil, wine and a pungent fermented fish sauce called garum from what is now modern Tunisia and Libya. Huge quantities of wheat were also imported from what were then the provinces of Africa Proconsularis and Egypt. The recent work has shown is that there was a particular preference for large scale imports of wheat from North Africa from the late 2nd century AD right through to the 5th and maybe 6th centuries. It is our belief that Portus and Ostia would have been home to a large expatriate population of North African trading families and commercial agents, the names of whom have been preserved on inscribed tombstone and career inscriptions. The population would have been very cosmopolitan and there would have been significant numbers of people from a range of ports and cities in Africa Proconsularis.

The recent geophysical discoveries have further emphasised how much less is known about Portus than neighbouring Ostia, and that there are many discoveries waiting to be unearthed which could augment the understanding of ancient Rome’s sophisticated trading network. These and other discoveries were presented at a workshop held at the British School at Rome on the 12th July, organized by Simon Keay (University of Southampton/British School at Rome) and Angelo Pellegrino (Soprintendenza Speciale per i Beni Archeologici di Roma).