We have discovered what we believe to be the remains of a medieval beachfront workshop in Grouville. Working alongside Jersey firms Sycamore Properties and Rok, we made the discovery while undertaking investigations at The Waves development at Keppel Tower.

Buried below over a metre of wind-blown sand, the well-made walls of the workshop had survived to several courses high. Pottery associated with the walls dated the structure to between the 12th and 14th centuries. At the northern end of the structure were the remains of an oven which appears to have been used for processing shellfish, especially limpets. The building appears to be using a silted-up Late Prehistoric ditch as a foundation.

Darryl Freer, Project Officer for Wessex Archaeology, said;

Upstanding remains of this period are rare on Jersey and, with subsequent analysis, may give us a unique insight into the industrial processes and inter-tidal exploitation practices of the time. The prehistoric remains were a surprise, as the footprint has been largely used as the foundation for the building, perhaps as it represented the most stable building conditions next to the shifting sands of the inter-tidal zone.

We have used a suite of scientific techniques to record the archaeology. The building itself was fully recorded using a technique known as photogrammetry, where hundreds of individual photographs are knitted together to create a photo-realistic virtual 3D model. In addition, samples have been taken for later analysis, to get a better understanding of the nature of the industrial processes on site. Pollen recovered from the samples will help us understand the wider environment, while monolith samples  will tell us more about the soil formation on the site.

Medieval wall remains uncovered in Grouville, Jersey Bronze Age ditch remains uncovered in Grouville, Jersey

Left Medieval wall remains and right Bronze Age ditch remains uncovered in Grouville, Jersey


The excavation was in response to a planning condition placed on the site by the Government of Jersey.

Tracey Ingle, Principle Planner Historic Environment, said;

The historic interest of the site was derived from the presence of Keppel Tower. This prompted a request for an assessment of the likely archaeological interest as part of the planning assessment of the site. The potential for archaeological interest was proven by earlier excavation, prior to demolition of the modern buildings. The current excavations were agreed within the car park footprint, allowing ongoing assessment of finds as the site levels within a protected and piled area were reduced.

Olga Finch, Curator of Archaeology at Jersey Heritage, said;

Jersey is so rich in archaeology and this exciting discovery demonstrates the importance and value of developer-funded archaeology to our Island’s planning system. Jersey Heritage is developing resources, such as the Historic Environment Record (HER) and the research framework, to ensure we can play our part in supporting that system. The new find illustrates the many chapters that make up Jersey’s fascinating and diverse story, much of it still hidden in the landscape waiting to be discovered.

The artefacts and environmental samples recovered from the excavation will be processed and analysed at our labs in Salisbury, as we seek to further understand the nature of the industrial processes being undertaken on the site during the Middle Ages.

Bruce Eaton, Project Manager for Wessex Archaeology, said;

Working away can be challenging at the best of times, but undertaking this tricky excavation away from the mainland and during a pandemic has added another layer of complexity for our team. I am incredibly proud of what they have managed to achieve and I am excited about sharing the results of our analysis with the people of Jersey in the near future.