Helfaut

A large village situated 4 miles south of Saint-Omer, at the D195 and D198 crossroads.It is located on a geological formation called the "plateau d'Helfaut", which separates the Aa valley to the north from the Lys valley, to the south. The commune is home to a unique geological heritage, resulting in an unusual landscape. The sides of the old quarries alongside the plateau display many geological strata. The quarries of Heuringhem and Blendecques have collapsed as a result of soil creep. The commune gave its name to 'Dilluvium d’Helfaut', a flint and clay formation rare in France and Europe.The commune is home to many rare and protected species in a heathland landscape, which is unusual for northern France and justified the creation of a nature reserve .

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