A battlement, in defensive architecture, such as that of city walls or castles, comprises a parapet, in which gaps or indentations, which are often rectangular, occur at intervals to allow for the launch of arrows or other projectiles from within the defences. These gaps are termed embrasures, also known as crenels or crenelles, and a wall or building with them is described as crenellated; alternative older terms are castellated and embattled. The act of adding crenels to a previously unbroken parapet is termed crenellation.

Buhen, alternatively known as Βοὥν (Bohón) in Ancient Greek, stands as a significant ancient Egyptian settlement on the western bank of the Nile, just below the Second Cataract in present-day Northern State, Sudan. Its origins trace back to the Old Kingdom period, where it served as an Egyptian colonial town, particularly recognized for copper smelting. In 1962, archaeological discoveries brought to light an ancient copper manufacturing facility encircled by an imposing stone barrier, indicating its origin during the rule of Sneferu in the 4th Dynasty. Inscriptions and graffiti disclosed a continuous Egyptian presence spanning two centuries, only to be interrupted by migration from the southern regions in the 5th Dynasty.