Château-Bas de Sedan, Prince's palace in Sedan, France

The Château-Bas de Sedan, also called the Palais des Princes, is a T-shaped building from the early 17th century, set slightly below the Château de Sedan. Its courtyard facade has paired pilasters, tall small-paned windows and dormers with alternating triangular and circular pediments; the city facade on the place du Château has eleven bays, vermiculated rustication and dormers topped with stone vases. The stone came from a nearby quarry.

On 15 April 1611 Jean Chardon, surveyor of Henri de La Tour, Duke of Bouillon, began building the palace after demolishing the old quartier du Moulin and earlier walls of the castle's lower courtyard. The plans were drawn by Salomon de Brosse, later architect to Marie de Médicis. It served as the princes' residence from 1614 to 1642, then housed the town's governor after Sedan joined France in 1642. From the Revolution it was a barracks; the moats were filled in 1878 and the carriage hall burned around 1880.

The name Château-bas (lower castle) distinguishes it from the fortress uphill, and the town-side portal was built to look like a city gate, once reached by a drawbridge over a moat. Inside, only a carved wooden-baluster staircase and a large cut-stone fireplace in the vaulted cellars survive from the original decoration, the rest lost during its use as a barracks after the Revolution.

The building stands on the place du Château, slightly below the Château de Sedan, and its city-facing facade opens onto that square. The moats were filled in 1878 and the drawbridge removed, so access is now level from the square through the monumental gateway. Inside, the vaulted cellars keep a carved wooden staircase and a stone fireplace.

The 1611 build replaced the old quartier du Moulin and the earlier walls of the castle's lower courtyard. Salomon de Brosse drew the plans, and Jean Chardon led the work for Henri de La Tour, duc de Bouillon, who moved in in 1614. The city-side portal, with its drawbridge, once formed the entrance to the whole castle complex.