Fortified castles were strongholds built during the Middle Ages to protect against invasions and attacks. They featured thick stone walls, towers, and moats, making them difficult to breach. These structures often served as residences for nobility and military leaders, providing safety for the inhabitants and their resources. The design of fortified castles varied by region, influenced by local materials and military needs. Many castles included features like drawbridges and arrow slits for defense. Famous examples include Neuschwanstein Castle in Germany and Edinburgh Castle in Scotland, which showcase the architectural ingenuity of their time.