Donjon de Châteaumur

The Donjon de Châteaumur is a medieval keep located in Les Châtelliers-Châteaumur (now part of the commune of Sèvremont), in the Vendée department of the Pays de la Loire region in western France. It stands on a granite promontory in the Gâtine bocage, not far from the Puy du Fou.

The barony of Châteaumur is mentioned as early as 950. It was a powerful lordship under the Vicomtes de Thouars and exercised rights of justice over some thirty-two surrounding parishes. The keep itself dates from the 12th century and belongs to the “Niortais” style, contemporary with and similar to the keeps of Pouzauges, Tiffauges and Noirmoutier.

Built as an independent stone fortress on a rocky outcrop, it was originally the only masonry structure on the site. A wooden or stone enclosure may have surrounded it in a roughly circular area. The entrance was placed at first-floor level and protected by a pivoting door that fitted into the wall. The interior was divided by a cross-wall for strength and comprised four levels: a basement and three floors carried on wooden beams. Provisions were stored on the ground floor; the first floor housed the seigneurial residence with fireplaces and latrines; the second floor probably served as a guard room with access to the hourds or battlements. A spiral staircase set in the south-east buttress linked the upper floors.

In the 14th century, during the Hundred Years’ War, an additional fortified enclosure was added. Parts of it remain visible today: houses around the square are built against the wall, and a fortified carriage gate (originally defended by a drawbridge) survives. The site suffered during the Wars of Religion and the Revolution (including the passage of the Colonnes infernales). The local churches were destroyed; the two former parishes of Châteaumur and Les Châtelliers were merged in 1825.

The keep is a large quadrangular tower measuring approximately 13 × 14 metres, reinforced by round buttresses at the four corners and a smaller buttress in the middle of each face. After a fire during the Revolution the walls were razed above the crenellations, leaving the ruin that stands today (about 12 metres high). The donjon and its gate were inscribed as a Monument historique in 1979.

The site is freely accessible from the exterior. Visitors can also extend their walk in the nearby Parc des Lavandières.