Machicolation

A machicolation (French:machicoulis) is a floor opening between the supporting corbels of a battlement, through which stones, or other objects, could be dropped on attackers at the base of a defensive wall. The design was adopted in the Middle Ages in Europe when Norman crusaders returned from the Holy Land. A machicolated battlement projects outwards from the supporting wall in order to facilitate this. A hoarding is a similar structure made of wood, usually temporarily constructed in the event of a siege. Advantages of machicolations over wooden hoardings include the greater strength and fire resistance of stone.