Crenellations on buildings
The act of crenellation is the cutting of crenels into a previously solid and straight parapet wall. Crenels are rectangular gaps or indentations which occur at regular intervals along the parapet, usually measuring 2-3 ft wide. Merlons are the solid widths between the crenels, usually measuring 4-5 ft wide and 3-7 ft high. Arrows and other missiles could be discharged from the parapet through crenels while taking defensive cover behind the merlons.
The presence of crenellations typically indicates that a castle or other building, such as a manor house, was constructed with features intended for defence against a battle or siege. In medieval England, a licence to crenellate had to be granted by the King or other regional authority before a property could be fortified.
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