Ancient Roman Breakwater Discovered Off Bacoli Coast!
A remarkable underwater archaeological discovery has emerged off the coast of Bacoli in southern Italy, where researchers have uncovered the remains of a Roman-era breakwater. What sets this structure apart is not just its age, but the fact that it was built using recycled architectural materials, providing new insight into ancient Roman maritime engineering and environmental adaptation.
The discovery was made at Portus Iulius, the Roman naval base at Misenum, once home to the Classis Misenensis, the most powerful fleet in the western Mediterranean during the Roman Empire. Famously, this was the fleet commanded by Pliny the Elder during the catastrophic eruption of Mount Vesuvius in 79 CE.
Photo Credit: Soprintendenza ABAP dell’Area Metropolitana di Napoli
Submerged between Punta Terone and Punta Pennata, the breakwater stretches approximately 90 metres in length and 23 metres in width, resting five to nine metres below the surface. It is composed of carved stone blocks, marble architraves, and fragments of cipollino marble columns, materials that were clearly not randomly scattered from collapsing buildings or victims of natural land movement (a common phenomenon in the area known as bradyseism). Instead, the construction was intentional, a sophisticated Roman response to harsh environmental conditions.
The wear on the stones, caused by marine borers and erosion, indicates that these architectural fragments once stood above sea level. Their reuse in forming a breakwater to defend against the Sirocco winds reveals a smart, sustainable approach to engineering, similar in purpose to modern coastal defences.
The recovery was led by the Italian Superintendency with assistance from the Carabinieri Underwater Unit and supported by cutting-edge technology, including 3D scanning, high-resolution photogrammetry, and hyperspectral imaging. These tools allowed archaeologists to map the site in fine detail before removal. In a first for Italy, the operation was live-streamed using Naumacos technology, developed by Gabriele Gomez de Ayala. Audiences could follow the process in real time via the Superintendency’s social media channels, bringing underwater archaeology directly to the public.
Photo Credit: Soprintendenza ABAP dell’Area Metropolitana di Napoli
Among the recovered materials are two decorated marble architraves and a cipollino marble column. These have now been moved to the Bourbon Park of Fusaro for desalination and restoration. Once conservation work is complete, the artefacts will be displayed in a new permanent exhibition at the historic Palazzo dell’Ostrichina, generously made available by the Municipality of Bacoli.
Superintendent Mariano Nuzzo, who oversaw the project, remarked that these materials likely originated from structures symbolising imperial authority, intimately connected to the fleet and political fabric of ancient Misenum.
This initiative follows a Memorandum of Understanding signed last year between the Superintendency and Bacoli Municipality, a joint commitment to safeguarding and promoting the submerged archaeological treasures of the Phlegraean Fields, considered one of the Mediterranean’s richest underwater heritage sites.
This discovery not only highlights the ingenuity of Roman engineers, drawing inspiration from earlier Hellenistic techniques, but also underscores the importance of combining advanced archaeological science with public engagement and heritage preservation. It’s a powerful reminder of how the past can still surface to inform, inspire, and connect us today.