The expression ‘Bay Salt’ was used throughout Northern Europe to describe the Atlantic sea salt produced in Brittany Bay, now called Bourgneuf Bay. Probably introduced by the Romans, salt production grew throughout the centuries reaching its highest point between the 14th and 18th centuries. Bay salt was exported to all the great ports of northern Europe: London, Amsterdam, Lübeck, Tallinn… In the 19th century the Bay ports gradually silted up and the salt trade faded away.

On the Pays de Retz coast, we find salt marshes at Bourgneuf, les Moutiers and Bouin resting on a unique base of blue clay. During the most prosperous times, the local population worked on tens of thousands of salt pans drawing in sea water through a complex network of channels and locks.

Every year over 200 ships weighed anchor in the Bay. For example, Tallinn in Estonia sent an annual fleet of 60 ships on a perilous round trip of more than 6000 km. Its purpose was to bring back the precious ‘white gold’ which was the only way to preserve meat and fish. The famous Baltic salted herring became a vital source of protein for a growing European population. Many ports and cities became wealthy and prosperous because of the salt trade.