A murder hole or meurtrière is a hole in the ceiling of a gateway or passageway in a fortification through which the defenders could shoot, throw or pour harmful substances or objects such as rocks, arrows, scalding water, hot sand, quicklime, or boiling oil, down on attackers. Boiling oil was rarely used because of its cost.[1]
- ^ Atzbach, Rainer (2015). "Castles at War" (PDF). The Danish Castle Research Association: 120–130.