Burh

A burh (Old English pronunciation: [ˈburx]) or burg was an Old English fortification or fortified settlement. In the 9th century, raids and invasions by Vikings prompted Alfred the Great to develop a network of burhs and roads to use against such attackers. Some were new constructions; others were situated at the site of Iron Age hillforts or Roman forts and employed materials from the original fortifications. As at Lundenburh (medieval London), many were also situated on rivers: this facilitated internal lines of supply while aiming to restrict access to the interior of the kingdom for attackers in shallow-draught vessels such as longships.

Burhs also had a secondary role as commercial and sometimes administrative centres. Their fortifications were used to protect England's various royal mints.

Burh and burg were Old English developments of the Proto-Germanic word reconstructed as *burg-s, cognate with the verb *berg-an ("to shut in for protection"). They are cognate with German Burg and Scandinavian borg and, in English, developed variously as "borough", "", and (particularly in the East Anglian region of England and Scotland) "burgh".

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