👉 A blockhouse is a type of military fortification constructed to defend against enemy attacks. These buildings are typically made of stone or brick and are often located on a hillside or surrounded by mountains, rivers, or other natural barriers. They were originally used by ancient civilizations such as the Greeks and Romans to protect their colonies from hostile forces. Today, blockhouses are still used in some countries for defense purposes, but they have been replaced with modern fortifications like towers and walls.