Moorfields was an open space, partly in the City of London, lying adjacent to – and outside – its northern wall, near the eponymous Moorgate. It was known for its marshy conditions, the result of the defensive wall acting as a dam, impeding the flow of the River Walbrook and its tributaries.
Finsbury Circus occupies the site of Moorfields proper, the Walbrook ran under what is now Blomfield Street, on its eastern side
The London Wall is a defensive wall first built by the Romans around the strategically important port town of Londinium in c. AD 200, as well as the name of a modern street in the City of London, England.
London Roman Wall – surviving section by Tower Hill gardens cross-section
A surviving fragment of the original 3rd-century Roman Wall in Cooper's Row near Tower Hill
Bastion 12, which is near the Barbican Estate, stands on Roman foundations with an upper structure of 13th-century masonry.
Yorkist forces attack the Lancastrians during the siege of London, 12–15 May 1471.