The Authie River is a river located in northern France. It flows through the Pas-de-Calais and Somme departments, eventually emptying into the English Channel. The river is approximately 100 kilometers long and is known for its picturesque landscapes and diverse ecosystems. The Authie River is significant for its role in local agriculture and wildlife. It supports various species of fish and birds, making it an important area for biodiversity. The river also serves as a natural boundary and is popular for recreational activities such as fishing and kayaking.