The Centre des monuments nationaux (CMN) is a French government body which conserves, restores and manages historic buildings and sites that are the property of the French state. It is run by the Ministry of Culture.

The Château de Coucy is a French castle in the commune of Coucy-le-Château-Auffrique, in Picardy, built in the 13th century and renovated by Eugène Viollet-le-Duc in the 19th century. During its heyday, it was famous for the size of its central tower and the pride of its lords, who adopted the staunchly independent rhyme: roi ne suis, ne prince ne duc ne comte aussi; Je suis le sire de Coucy.