Doucier is a commune in the Jura department in Bourgogne-Franche-Comté in eastern France. The western shore of Lac de Chalain is ho…Doucier is a commune in the Jura department in Bourgogne-Franche-Comté in eastern France. The western shore of Lac de Chalain is home to one or more prehistoric pile-dwelling settlements that are part of the Prehistoric Pile dwellings around the Alps UNESCO World Heritage Site.