A murder-hole is a hole in the
ceiling of a
gateway or passageway in a
fortification through which the defenders can fire, throw or pour dangerous or noxious substances at attackers. As a result, the defenders would be able to rain
rocks,
arrows, boiling water, heated
sand and other substances down on the attackers' heads. There is little evidence for the widely held belief that
boiling oil and molten
lead was used for this purpose.
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A hole cut in the roof of passages needing defense, such as in gatehouses or along the top of curtain walls. Through murder holes could be poured hot water, oil, stones or
archers could fire through them wrecking havoc on the assaulting troops.