The hâble d'Ault swamp

In the Middle Ages, the Ault harbour or " Hâble d’Ault» was an important anchoring area for the ships which could enter this zone by means of a channel that was connected with the sea.

Besides, Le Hâble d' Ault was considered as one of the biggest fishing centres of Northern France insofar as the quantity of fish gathered (soles and plaices mainly) was sizeable.

In spite of its rich historical past, nowadays the swamp of “Le Hâble d' Ault” is essentially known for the wealth of its wild fauna and flora: indeed, more than 270 species of migratory birds have been listed since the end of the 19th century as well as nearly 250 species of plants, some of which are protected at the national level such as the sea kale.

The other characteristic of this swamp is that it is only separated from the sea by an offshore bar of pebbles whose base is about 80 meters large. These pebbles, which make up an offshore bar that protects the swamp from the assaults of the sea, is in fact the result of the slow erosion of the cliffs of chalk and flint of the Norman coast.

During the crumbling of the cliff and under the effect of the swell, blocks of flint will break up and be polished and eroded, which will give them their round shape: the pebble.

The pebbles whose silica content is close to 95% allow the creation of a multitude of by products: bathroom furniture, false teeth, road painting, etc. and thus make of Cayeux-sur-Mer the world capital of pebbles, as no pebble in the world possesses the same properties.