Salterns are sites where the salt workers collect approximately 15 000 tons of cooking salt a year, and approximately 300 tons of Fleur de sel or "flower of salt". A cooperative promote quality with a label (the French Label rouge). Today around 250 workers live on the salt marshes. These salterns are also classified as ""remarkable Sites of taste"". The principle is simple. Channels that feed the water reservoirs with sea water, use the tides. Salty water then evaporates in different dams till there are only a few centimeters of sea water left. The last step is where the salt crystallizes and produces the fleur de sel and coarse salt.