Châtillon-sur-Seine is a commune of the Côte-d'Or department, eastern France. The Musée du Pays Châtillonnais is housed in old abbey of …Châtillon-sur-Seine is a commune of the Côte-d'Or department, eastern France. The Musée du Pays Châtillonnais is housed in old abbey of Notre-Dame de Châtillon, within the town, known for its collection of pre-Roman and Roman relics.