Cancale oysters come from the beds in the Bay of Mont-Saint-Michel an hour north of Rennes, flat plates and cupped creuses that carry an iodine bite from a fourteen-metre tide.
Cancale has been an oyster town since Roman times and supplied the French court from the seventeenth century onwards; the flat native oyster, the plate, was dredged wild until overfishing and disease all but destroyed the beds in the twentieth century. Cultivated creuses now make up most of the harvest, grown on trestles in the bay and finished in some of the strongest tidal currents in Europe, which is what gives them their firmness and their salinity. Rennes eats them without ever going to Cancale: the oysters travel the sixty kilometres inland the same morning and land on the Marché des Lices stalls and the seafood counters in town.
