The underwater archaeology of Fourni, Greece’s shipwreck capital of the world

The archipelago of Fourni, an insignificant group of Greek islands in the Aegean, lies at the crossroads of ancient north-south trade routes connecting the Black Sea to Alexandria and the eastern Mediterranean and east-west routes to Spain and Italy. 

“Despite the sheer number of wrecks found, Fourni isn’t naturally a dangerous place,” says Peter Campbell, a British School at Rome archaeologist and co-director of the Greek-American expedition. “Because the vessels sank complete with their cargoes, what we see in the 53 wrecks we have discovered so far is an incredible snapshot of trade over 25 centuries.”

Campbell believes his team in Rome, and at the RPM Nautical Foundation in the US, working with the Greek Ephorate of Underwater Antiquities, have many more shipwrecks to find in the area. “Fourni has already added over 24 per cent to the list of known ancient shipwrecks in Greek territorial waters and we still have much more of the seabed to search. Fifty per cent of the coastline remains to be explored by our divers, and we have only surveyed 5 per cent of the deep water areas,” he adds.

The sheer number of wrecks reflects the large volume of traffic through this maritime navigational choke point in the Eastern Mediterranean. In a way, it is like comparing statistics of car accidents on a dangerous road and a good road, to find that accidents are higher on the good road. This can only happen if the number of cars travelling along the good road is considerably larger.

Campbell first arrived in Fourni when conducting ethnographic research with local sponge divers in Kalymnos, a village on one of the Fourni group. “We made a map of the region and marked where the sponge divers had seen shipwrecks. The results were so promising that I went to meet George Koutsouflakis from the Greek Ephorate of Underwater Antiquities in Athens. He too had a map from local Fourni fishermen of possible wrecks around the island. We decided to explore the island together. That was back in 2015 and we have not been able to leave Fourni since, there are so many shipwrecks there,” says Campbell.

His and Koutsouflakis’s low-tech, low-cost, people-based approach has delivered wrecks at 50 per cent of the sites they were told about. These interviews with fishermen and divers were critical to getting the project off the ground.

Fourni is not an obvious place to search for ancient wrecks. It has never been home to any ancient trading cities, only a few fishing villages; and even references to the islands are very sparse in ancient literature, so it’s not likely the islands would have attracted the attention of marine archaeologists for hundreds of years to come, if ever.

“What we are seeing are the very unlucky few,” says Campbell. “Many of the wrecks have clearly been anchored up, sheltering in the lee of the cliffs from the prevailing northerlies. All it takes is for that wind to swing around to the south quickly when the crew is asleep or not alert and the vessels will be blown into the base of the cliffs. Many wrecks show the same unfortunate pattern, a smashing and falling back, scattering their cargoes from the shallows into the deep.”

Most of the time, wreck-hunting marine archaeologists use expensive sonar-equipped ships, capable of holding a geostationary position so robotic remotely operated vehicles, or ROVs, can search the seabed while tethered to the ship. These specialised vessels are both expensive and hard to charter at short notice. The team used the RPM Nautical Foundation’s ship Hercules in 2017 to explore an area of seabed which is too deep for human divers, but have had limited success to date.

“What is astonishing about Fourni is not only the number of the shipwrecks, but also the diversity of the cargoes, some of which have been found for the first time on any ancient shipwrecks,” says Campbell’s Greek co-director Koutsouflakis. “We intend to be working at this site for at least another 10 years; there is so much to be documented, we could easily end our careers here,” added the 49-year-old, laughing.

Right now, Koutsouflakis and Campbell are busy documenting what is turning out to be the shipwreck capital of the world. Ultimately the Ephorate may decide to select one of the many wrecks that would make a major contribution to historical and archaeological knowledge, containing a rare or unique cargo, being well preserved with an extensive part of the hull remaining, and accessible and safe to excavate in its entirety.

“If we have the finance in place for a total excavation of a cargo and the shipwreck’s hull, the best case scenario is a 5- to 10-year operation taking us into the 2020s,” says Koutsouflakis. To put the magnitude of the importance of the finds at Fourni into context, the US is proposing a national marine sanctuary in Lake Michigan to protect 39 known shipwrecks in 875 square miles of water. Fourni now has 53 known wrecks in only 17 square miles, and that number is only expected to rise.

Obviously all organic matter carried by the ships such as grain has long since been eaten by sea creatures. The large clay amphoras – the biggest originate from the Crimea and hold 70 litres – now lie empty, but their shape and design tell us of their port of origin, their original contents and direction of trade in ancient times. It is clear there was a significant international wine trade with wines from Spain and Italy exchanged widely. Like today, wines or olive oil of quality travelled far, while poorer wines and oils were consumed near to home.

Another common find is containers that held garum, a fermented fish sauce, a favourite Greek and Roman condiment similar to soy sauce. Garum was hugely popular in Roman cuisine and has been found in cargoes coming from North African wrecks. Another wreck carried dinner plates dating to the late Roman period.

‘The danger is always there, some wrecks were already looted, but the inhabitants of Fourni are aware of their marine heritage and are determined to protect it.’

When working on site, the daily routine for the team involves a weather report check at about 6.30am to see where will be safe to work that day. Breakfasting together, the divers and conservation staff plan the day and split into two teams working from boats on opposite sides of the island if wind conditions permit. The divers will make up to two dives a day, down to a maximum depth of 45m on air, decompressing in stages using mixed gases ascent, finishing with pure oxygen in the shallows to flush out the remaining nitrogen absorbed by their bodies at depth.

“The underwater visibility is incredible, usually 20m or more,” says Campbell. “We have no difficulty spotting artefacts or wreck remains at all. The conditions are about as ideal as you can get. As an archaeologist, I could not have dreamed of a better place to work.”

Each site is recorded, meticulously photographed and measured using a technique called photogrammetry. Digital underwater cameras and strobes record an overlapping mosaic of images, which can subsequently be post-processed by software to create a centimetre-accurate 3D model of each wreck site. This is known as photo-mosaicing.

These images record the state of each site, which can be checked for deterioration or disturbance over time, and of course can be interrogated by archaeologists of the future who won’t even have to get wet.

In deeper areas inaccessible to the divers, RPM Nautical Foundation’s research vessel Hercules uses remote sensing equipment and ROVs to survey the bottom topography and assist in the survey and documentation of the shipwrecks. Key tools are the hull-mounted multi-beam sonar, which gives the archaeologists a high-resolution map of the seafloor down to 90m. To date, only 5 per cent of the deeper waters have been surveyed in this way.

Every item to be removed from the seabed is assessed by experienced conservators from the Ephorate before it is raised to the surface. Angelos Tsompanidis leads the team of five conservator divers working at Fourni. “First we record the position of the find underwater using photos and sometimes photo-mosaicing to give us a 3D picture of the artefact in situ,” he says. “Items may already be broken or very delicate. We record the precise location and conservation status of the object, and with the archaeologists, we decide whether to raise it to the surface or leave in place until we can conserve it safely. We then provide any necessary first aid, remove it from agglomerates and recover to the surface.”

Tsompanidis’ team works from a temporary laboratory base on the harbour quayside of the main town. “Ideally, we would use freshwater to start the salt removal process, but that is in very short supply on Fourni, so the aim is to keep artefacts from drying out by immersing them in seawater. We clean them delicately with both hand and pneumatic tools – one is a bit like a pencil with compressed air supplied to the tip so that we can remove concretions and living animals.”

The next phase of conservation is gradual removal of salt from the artefacts, which takes place once everything is safely removed to Athens. Growing salt crystals can destroy surface details in ceramics and must be leached out slowly in huge freshwater tanks. The desalination process can take up to a year.

Since the Greek financial crisis, Tsompanidis must work alone on the Fourni artefacts to prepare them for exhibition and further study, as there are no funds available for additional staff. The Fourni Underwater Archaeological Project is actively seeking sponsors for this phase of the work, vitally important to prepare the recovered artefacts for exhibition or scientific analysis, which may reveal further information about trade and exchange in ancient times.

Like their counterparts on dry land, underwater archaeological sites are a finite, irreplaceable and fragile part of our cultural heritage. It’s a race against time to secure finds and recover at least a sample of the precious artefacts contained in cargoes, as they are at high risk of looting. The technology used to detect shipwrecks is equally available to looters, who may be better financed. That’s why the archaeologists take a sample of the cargo in case the shipwreck ‘disappears’ from the sea floor. It means at least a representative record of its cargo is retained.

Of course, every marine archaeologist hopes for a huge find like a warship, or a ship carrying statues or other works of art, but realistically, given the rate of heritage theft, these could already have been stolen. Koutsouflakis says: “The danger is always there, some wrecks we located were already looted. But now, the inhabitants of Fourni, after three seasons of research, are aware of the importance of their marine heritage, which has transformed their tiny island into a place of great historical significance and they are determined to protect it.”

It is not unknown for divers intent on theft to desecrate a site, stripping everything down to the wood, leaving a skeleton of the ship. Technology can help by showing any disturbance of the wrecks from season to season, but the low-tech solution is combined effort of the port police and local fishermen, who now help to protect shipwrecks from pillaging by alerting authorities to any unusual activity in the area. They are incredibly proud that Fourni is now firmly on the map of Greece’s cultural heritage, and hope to attract new visitors by raising funds to exhibit some finds in a small museum.