Château du Nessay, Coastal castle in Saint-Briac-sur-Mer, France.

Château du Nessay is a former castle on a peninsula now functioning as a hotel with 17 rooms spread across the main building, annexes, and outbuildings. The property features a restaurant, bar, Phytomer spa with sauna and hammam, and provides direct access to the beach and hiking trails.

The present château was built in 1882 by architect Alexandre Leroyer of Saint-Servan for Count Maurice Goislard de Villebresme, who became the town's first secondary resident mayor from 1892 to 1899. It replaced a 12th-century fortified castle called La Houle, held by the d'Elbiest family from 1460 to 1520 and demolished around the mid-17th century. Wings were added in 1896 and 1908. In 1914 it passed to Georges Bergès, inventor of the cheddite explosive; occupied by German forces in World War II, it was recovered in ruins, sold to Gillet Thaon as a holiday camp, then bought by the municipality in 1974. After a 2017-2018 renovation by Kaahotels, the first hotel guests arrived on 27 July 2018.

The name Nessay derives from the old site name "La Houle"; the 1828 cadastral register records the former guardhouse as the "prison du Nezay". That 18th-century guardhouse, built of granite and rubble with a stone-covered roof, became a prison during the Revolution, then was converted into the castle chapel by Villebresme, who reused a 16th-century door in it. Since 2018 it has served as a small food store.

The château stands on a small peninsula between the beach and port of Le Bechet to the east and the Grande Salinette beach to the west, so it can be reached on foot from both. The building is now a hotel and restaurant; the chapel, once a guardhouse, serves as a food store and is not open to visitors.

The 18th-century corps de garde just south of the château became a prison during the Revolution and appears as "prison du Nezay" in the 1828 cadastre. Villebresme turned it into a chapel, reusing a 16th-century door; since 2018 it serves as a food storeroom for the hotel.