Charente-Maritime: the Broue tower of Saint-Sornin, a medieval treasure to understand the environment of yesterday

For the past ten years, the Broue Tower in Saint-Sornin has been a site of archaeological studies. A way for researchers to learn more about the evolution of the region's landscape since the Middle Ages.

The 2025 excavation phase at the Broue Tower in Saint-Sornin has come to a close: an opportunity to revisit the site's archaeological significance. Under study since 2015, this unique site in Charente-Maritime, thanks to its chapel and stately home, offers an opportunity to explore the lifestyles of its inhabitants in the Middle Ages. Used between the ^11th and ^15th centuries to monitor the salt marshes, it bears powerful witness to the period and the place. Even more astonishingly, it also offers the opportunity to retrace the surrounding topography.

For Éric Normand, the archaeologist in charge of the project , this opportunity to study environmental changes during the Middle Ages is a real opportunity. "It's rare to have data like what we find here to study biodiversity in the Middle Ages. What's interesting then is to be able to compare them with the landscapes we have today." To advance this field of study, Benoit Clavel, an archaeozoologist specializing in the Middle Ages, is participating in the excavations. "We have areas where we find a lot of food waste from the lords who lived in the dwellings. This allows us to understand both their standard of living, but also the topography of the places." The researcher was able to observe an evolution in the birds and fish that were consumed, which suggests that the environment of the hunting and fishing areas evolved over the centuries, becoming less and less maritime.

Even though studies are progressing, many hypotheses remain difficult to prove. "This year's discoveries have brought us more questions than answers," laughs the site manager. One of these questions concerns the possible use of the site as a monastery: "The rectangular, self-enclosed structure could be reminiscent of a monastery, and we've found marked pots that also point us in that direction."

In addition to its historical interest, the site also has educational significance. Indeed, among the twenty or so volunteers who come to participate in the excavations, a number are still students. "We have a lot of archaeology or art history students. Now, in their curriculum, most have a practical component to validate, with an internship or hours spent on a construction site."

One of the big questions surrounding the site now is: what will become of it after the excavations are over? For Éric Normand, if the public authorities want to make it a tourist and heritage site, this is a question that must be asked now. "We often find ourselves with excavation sites where, at the end of the research, we look back without knowing what will become of them. Developing this type of site is something that takes time; we need to think about it now."