The Sedan medieval castle, or high castle, is located on a promontory along the Meuse river. Built in 1424 by Lord Evrard II de La Marck, it was expanded and strengthened over the centuries. In the centre of the main courtyard, the remains of the Saint-Martin church, built in the 11th century by the monks of Mouzon Abbey, are still clearly visible. Turned into the castle’s chapel, it stood until its destruction between 1822 and 1825, to be replaced by a cannonball park. The castle was then a citadel with no palatial function, transformed into barracks by the French army.