Nans is a commune in the Doubs department in the Bourgogne-Franche-Comté region in eastern France. Nans lies 5 km from Rougemont at t…Nans is a commune in the Doubs department in the Bourgogne-Franche-Comté region in eastern France. Nans lies 5 km from Rougemont at the foot of a high, horseshoe-shaped cliff.