Battlements, Merlons, Embrasures and Crenels

The term battlements refer to the top of a fortified construction, whether that is the curtain wall, a tower or the keep for example. The typical shape of the battlements consisting of sections of stone with gaps inbetween is known as crenelations.

The sections of wall are known as merlons and the gaps are known as either embrasures or crenels. The purpose of the design was to protect the defenders from arrows and other missiles fired by enemies.

In the later medieval period castle owners had to seek permission from the king to fortify buildings and add battlements. The term used for this permission was 'licence to crenelate'.

Arrow Loops

A development that gave more protection to the defenders on the battlements was the introduction of arrow loops. These were slots through which archers could fire their arrows without having to stand in the gaps of the battlements. The arrow loops were wider on the inside than the outside and were angled downwards so that the archers could fire down at the attackers on the ground.