Saint-HerninSaint-Hernin is a commune in the Finistère department of Brittany in north-western France. The historian and librarian Georges Le Rider was born in Saint-Hernin.WWW saint-hernin.comPopulationInhabitants of Saint-Hernin are called in French Saint-Herninois.GeographySaint-Hernin lies on the northern slope of the Montagnes Noires. The canal de Nantes à Brest, which is the canalized river Hyères, forms the commune's northern border.