Medieval fortification

Medieval fortification refers to medieval military methods that cover the development of fortification construction and use in Europe, roughly from the fall of the Western Roman Empire to the Renaissance. During this millennium, fortifications changed warfare, and in turn were modified to suit new tactics, weapons and siege techniques.

Towers of medieval castles were usually made of stone or sometimes (but rarely) wood. Often toward the later part of the era they included battlements and arrow loops. Arrow loops were vertical slits in the wall where archers from the inside shot arrows through at the attackers, but made it extremely difficult for attackers to get many arrows back through at the defenders. The tower had a spiral staircase to make it hard for the attackers to fight upward but very easy for a defender to fight downward if they were right handed.

An exact nature of the walls of a medieval town or city would depend on the resources available for building them, the nature of the terrain, and the perceived threat. In northern Europe, early in the period, walls were likely to have been constructed of wood and proofed against small forces. Especially where stone was readily available for building, the wood will have been replaced by stone to a higher or lower standard of security. This would have been the pattern of events in the Five Boroughs of the Danelaw in England.

In many cases, the wall would have had an internal and an external pomoerium. This was a strip of clear ground immediately adjacent the wall. The word is from the late medieval, derived from the classical Latin post murum, "behind the wall."

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