Boulogne

The river Boulogne is located in western France in the départements Loire-Atlantique and Vendée. It is 86. 5 km in length and flows north from the source near Saint-Martin-des-Noyers, through Les Essarts and La Merlatière, then through Boulogne, Vendée and Les Lucs-sur-Boulogne into the Lac de Grand-Lieu.