donjons

A donjon is a term used in medieval castle architecture to denote the principal fortified tower, or keep, of a castle. It is typically the strongest part of the fortress and often served as the lord's residence, as well as a last line of defense during a siege. The word derives from Old French donjon, and in English historical writing it is commonly used as an equivalent of 'keep'.

Construction and form: Donjons are tall, stone-built structures integrated into the castle's defensive scheme. They are usually square or polygonal in plan, though circular keeps occur in some regions. Thick walls, narrow slits for arrows, and limited doorways are typical, and the donjon often contains living quarters, storerooms, and a chapel. The keep might be connected to other parts of the castle by galleries and staircases, and it could overlook the curtain walls and gatehouse.

Distinction: The donjon is not a dungeon; while the latter denotes a subterranean or prison chamber, a donjon is predominantly above ground and served as residence and fortress. In later medieval and modern usage, the term 'donjon' appears mainly in historical or literary contexts, while 'keep' is more common in general English.

Historical role and distribution: Donjons were built across much of medieval Europe, with regional variations in style and size. They reached their peak in the High Middle Ages as castles grew more elaborate and the keep became the symbolic centerpiece of the fortress.

Legacy: Today surviving donjons remain architectural monuments and are studied for medieval military architecture. In popular culture, the term is used in literature, film, and games to evoke medieval fortresses.