Watch tower

A watchtower, or watch tower, is a type of fortification used in many parts of the world. It differs from a regular tower in that its primary use is military, and from a turret in that it is usually a freestanding structure. Its main purpose is to provide a high, safe place from which a sentinel or guard may observe the surrounding area. In some cases, non-military towers, such as religious pagodas, may also be used as watchtowers.

The Romans built numerous towers as part of a system of communications, one example being the towers along Hadrian's Wall in Britain. Romans built many lighthouses, such as the Tower of Hercules in northern Spain, which survives to this day as a working building, and the equally famous lighthouse at Dover Castle, which survives to about half its original height as a ruin.

In medieval Europe, many castles and manor houses, or similar fortified buildings, were equipped with watchtowers. In some of the manor houses of western France, the watchtower equipped with arrow or gun loopholes was one of the principal means of defense. A feudal lord could keep watch over his domain from the top of his tower.

In southern Saudi Arabia and Yemen, small stone and mud towers called "qasaba" were constructed as either watchtowers or keeps in the Asir mountains. Furthermore, in Najd, a watchtower, called "Margab", was used to watch for approaching enemies far in distance and shout calling warnings from atop.

Scotland saw the construction of Peel towers that combined the function of watchtower with that of a keep or tower house that served as the residence for a local notable family.

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