Burh

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.

Burh and burg were Old English developments of the Proto-Germanic word reconstructed as *burg-s, cognate with the verb *berg-an[1] ("to shut in for protection").

Most of these were founded by Alfred the Great in a consciously planned policy that was continued under his son Edward the Elder and his daughter, Æthelflæd, the 'Lady of the Mercians', and her husband Æthelred, Ealdorman of Mercia.

[7] A tenth-century document, now known as the Burghal Hidage and so named by Frederic William Maitland in 1897, cites thirty burhs in Wessex and three in Mercia.

[8] Only eight of the burhs achieved municipal status in the Middle Ages: Chester, Bridgnorth, Tamworth, Stafford, Hertford, Warwick, Buckingham and Maldon.

[11] The burhs were made in a variety of different ways, depending on materials available locally, and the size of the settlement or area it was intended to defend.

Sometimes, old Roman walls were simply repaired, as in towns such as Winchester, Exeter, York, Burgh Castle, Portchester and Dover.

Substantial new towns were built on flat land with a rectangular layout, at for example Oxford, Wallingford, Cricklade and Wareham.

[14] Thus with this integrated network of fortifications and defence with the burhs at its centre, Alfred was able to make it difficult for the Vikings to seize strategically important towns and ports.