Originally surrounded by a wall which was destroyed in 1750, this castle dates from the second half of the 12th century. Its construction is probably the work of Guillaume de Mandeville, who was loyal to Henri II. After 1204, the castle was given by Philippe-Auguste to his marshal Henri Clément.
This rectangular keep (21.40 m by 15.40 m on the exterior) is the best preserved in Normandy. It is built in small bonding with joints sometimes forming a sort of coating, and its four walls are intact and rise to 25.70 m; their summit was given a gallery of machicolations and crenelations in the 14th century. The four corners are reinforced by square turrets in limestone freestone, which protrude only a little, giving them their buttress-like appearance.
Squeezed in on the large south-eastern side there is a smaller construction which housed the entrance located on the first floor.
The keep is divided into three floors: a ground floor without windows and two other levels which are pierced on the north-west face, by a geminate window. Each of these is built from a single non-vaulted piece whose floor rested on the cornice brackets or on wall recesses and wooden pillars. Each floor had a large chimney.
- Desvaux A., Le château de Chambois, Bulletin historique et archéologique de l'Orne, t.XXI, 1902, p. 260-261
- Deschamps P. , Le donjon de Chambois, Congrès archéologique de France, CXIe session, 1953, p. 293-308
- Musset L., Le château de Chambois, Annuaire des cinq départements de la Normandie, Congrès d'Alençon, 122e congrès, 1964, p. 54-55
- Châtelain A., Donjons romans des pays d'ouest, Paris, Picard, 1973, p. 122-124
- L'art roman dans l'Orne, Art de Basse-Normandie, n° 66, été 1975, p. 39
- Decaëns J., Le château de Chambois, in : L'architecture normande au Moyen-Age, t. II, Caen-Condé, 1997, p. 320