Stone Keep is a type of medieval fortification characterized by its strong, stone walls and towers. These structures were often built on elevated ground to provide a strategic advantage against attackers. The design typically includes a central building, known as the keep, which served as the residence for the lord and a refuge during sieges. The construction of Stone Keeps began in the 10th century and continued into the 15th century. They were essential for defense and often featured thick walls, narrow windows, and a gatehouse. Many Stone Keeps are now historical sites, offering insight into medieval architecture and military strategy.