Castle architecture refers to the design and construction of fortified structures built primarily during the Middle Ages. These castles served as residences for nobility and military strongholds, featuring thick stone walls, towers, and moats for defense. Common elements include the keep, a central stronghold, and battlements, which provided protection for archers. The layout of a castle often included a courtyard, living quarters, and storage areas. Architectural styles varied by region, with examples like the Norman castles in England and the château style in France. Castles were not only military fortifications but also symbols of power and prestige.