Château de Sedan (link, enlace, lien).
The Château de Sedan is a castle situated in Sedan, France, on a headland on the border of the river Meuse, in the Ardennes département of France. Solid and imposing, Sedan castle dominates the town with its impressive stature. It took one and a half centuries, starting in 1424 and with successive additions, to build this monument, the largest feudal fortress in Europe. In 1424, in the early 15th century, Evrard d'Arenberg, Count of Marck, began building a very powerful castle on a rocky outcrop around the remains of the church of St. Martin. This castle, consisting of a large number of towers and buildings built over several centuries, was part of the Principality of Sedan where several La Marck princes succeeded each other over half a century.