The Barbican 


Click for my NHS History site      link to NHS History


The City Wall in the Barbican Area

This was written by

Jenny Hall
Roman Curator
Department of Early London History & Collections,  Museum of London

The Romans originally built the City wall in about AD200. It was 3.2km in length stretching from the site of the later Tower of London around to Blackfriars. It enclosed an area of 330 acres – the size of the Roman town. An earlier building, however, occupied the Cripplegate area. This was the Roman fort, built in about AD110.  The fort was constructed away from the main area of the town, perhaps on the orders of the emperor Hadrian who disliked soldiers being billeted with the local townspeople. The fort was rectangular in shape, covering 12 acres. It had one gate in each side and internal turrets leading to the sentry walk. The stone-built walls of the fort were 1.2m thick and 4.5m high. The fort was not a defensive measure but was probably built to house the soldiers based in Londinium – those working on the governor’s headquarters staff as clerks, military policemen and guards. Also it provided a resting point for soldiers on their way to the rest of the province of Britannia.  

When the City wall was constructed, therefore, the fort was already in existence and the fort walls had to be extended to bring it up to the same height and width as the City wall. The City wall was built 2.7m in width at its base, tapering to 2.4m. Although the surviving remains show a height of 4.4m, the original height of the wall would have been about 6m high, including the sentry walk. The wall was constructed as two parallel walls of shaped, squared blocks of ragstone, brought by boat from the Medway area of Kent. The Roman laid some 3, 4, or 5 courses before filling the cavity with ragstone rubble and mortar. Large flat clay tiles were then laid across the structure for stability and then further courses were constructed on top in the same fashion until the wall reached the required height. It has been calculated that at least 1 million squared blocks of stone would have been needed for the wall’s construction and would have required skilled labour.  

Gates were included in the wall at Aldgate, Newgate and Ludgate as well as using the existing gates in the fort at Cripplegate. Later in the Roman period, Aldersgate was added to avoid using the west gate of the fort. A gate was added at Moorgate in the medieval period.  

The landward wall remained the only defence until a riverside wall was constructed in the late 3rd and 4th centuries on the line of present-day Thames Street. Unlike the landward wall, the riverside wall was of different construction, in some areas re-using large stone blocks removed from dismantled structures. Semi-circular towers, bastions, were added in about AD350-364. These towers were 8-9m high sited about 60m apart of the eastern side of the City wall and were solid in construction. Like the riverside wall, they re-used building material, stripping the cemeteries that lay beyond the City wall of their tombstone monuments.  

In the medieval period, the Roman wall was still in existence and was still used for defensive purposes. The wall was rebuilt and heightened but basically remained Roman at the core. The City gates remained in use until the restoration of Charles II. In 1660 the gates were unhinged and the portcullises were wedged open. Towers, three storeys high, were constructed as part of a rebuilding programme initiated by Henry III in 1257 on the western side of the landward wall. They were built as hollow  semi-circles with arrow slits as windows and wooden floors. They were rented out to hermits and in the later medieval period both towers and gates were rented out as houses. 

In the Cripplegate area at St Alphege gardens, a church was built onto the wall in the 11th century and the wall was rebuilt with brickwork battlements during the War of the Roses in 1477. The lake at Wallside mirrors the medieval City ditch while the medieval bastion on the corner is a 13th-century tower built onto the north-west corner of the Roman fort. At Barbers Hall, a 29m stretch of wall is Roman, medieval and later in date. Buildings began to encroach on the wall during the 13th – 16th centuries. In 1607, the Barber-Surgeons built their courtroom incorporating an earlier medieval tower. The semi-circular tower provided the dais to the courtroom. In the 1630’s more buildings including Inigo Jones’ lecture theatre (built 1636). The Hall in Monkwell Street used the City wall as its west wall. In the 18th century, the tower (outside the Museum) was converted into a house and its internal features can be seen as a brick staircase leading up to the first floor. In 1872 the whole area was redeveloped into warehouses and remained so until the area’s destruction in the Blitz of 1940.