In medieval fortifications, machicolations (derivation French: machicoulis) are openings in the upper sections of castles or other fortifications through which missiles, boiling oil and other objects could be thrown down onto attackers. The openings could be in either the vertical plane or in the floor.
In Italy they are known as ‘piombatoio’, in France ‘meurtriers’, and in England ‘murder holes’ and ‘drop boxes'.
They originated in Syria but the idea was transplanted to Europe by returning Crusaders. One of the earliest examples dates from the 13th century and can still be seen at Chateau de Farcheville, near Paris. Since the Medieval period they have been mostly restricted to decorative purposes.
The openings, usually as narrow as possible to minimise the chances of arrows hitting defenders, usually occur where a parapet extends outwards on corbels so as to project from the face of the wall; this gave the defenders a better top view of assailants and allowed more accuracy in dropping rocks and boiling liquids down onto their heads. Either to deceive the enemy or for aesthetics – or both – a parapet might have been extended outwards on corbels even if there were no machicolations behind.
Machicolations were best located above critical points, such as gateways and entrances but could also form a continuous line extending around a castle. They were common in French castles but in their UK counterparts were usually restricted to the areas above gateways, eg Conwy Castle, Wales, built 1283-1289.
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