Arrow slits are narrow openings in the walls of castles and fortifications, designed for archers to shoot arrows while remaining protected. These slits allowed defenders to see and target enemies without exposing themselves to direct fire. The design typically features a wider interior and a narrow exterior, maximizing visibility and minimizing vulnerability. Commonly found in medieval architecture, arrow slits were crucial for defense during battles. They are often associated with castles and fortresses, where they provided a strategic advantage. The use of arrow slits reflects the importance of fortification in military tactics during the Middle Ages.