London wall

London Wall was the defensive wall first built by the Romans around Londinium, their strategically important port town on the River Thames in what is now London, England, and subsequently maintained until the 18th century.

It is now the name of a road in the City of London running along part of the course of the old wall between Wormwood Street and the Rotunda junction where St. Martin's Le Grand meets Aldersgate Street. Until the later Middle Ages the wall defined the boundaries of the City of London.

Although the exact reason for the wall's construction is unknown, the wall appears to have been built in the late 2nd or early 3rd century. This was around 80 years after the construction in 120AD of the city's fort, whose north and west walls were thickened and doubled in height to form part of the new city wall. It continued to be developed until at least the end of the 4th century, making it among the last major building projects undertaken by the Romans before the Roman departure from Britain in 410. Reasons for its construction may have been connected to the invasion of northern Britain by Picts who overran Hadrian's Wall in the 180s. It may be linked to the political crisis that emerged in late 2nd century when the governor of Britain Clodius Albinus was consolidating his power after claiming the right of succession as Roman emperor. After a struggle with his rival, Septimius Severus, Albinus was defeated in 197AD at the Battle of Lugdunum (near Lyon, France). The economic stimulus provided by the wall and Septimius's subsequent campaigns in Scotland improved Londinium's financial prosperity in the early 3rd century.

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