London Wall: section of Roman wall and Roman, medieval and post-medieval gateway at Aldersgate

Reasons for Designation

London Wall was constructed as part of an extensive programme of public works between approximately AD 190 and AD 225. It served to form the basis of the protection of the town far into the medieval period, and was also a key factor in determining the shape and development of both Roman and medieval London. The uniformity of design and construction of the 2nd century wall suggests that it was planned and built as a single project. It enclosed the whole of the landward side of the town from Tower Hill to Blackfriars, incorporating an existing military fort at Cripplegate. It was laid out in straight sections, linking the major routeways into London, and gateways were constructed at the points of entry at Aldgate, Bishopsgate, Newgate and Ludgate. The defensive nature of much of the Wall's circuit was strengthened by an external ditch, with the exception of those areas where the marshland around the Walbrook acted as a natural defensive feature. Internally, it was strengthened by a bank of earth. The Roman Wall was built on a trench foundation of puddled clay, and included a rubble core interspersed with bonding tile courses. It is known to have stood to a height of approximately 4.4m above a sandstone plinth, and is believed to have been surmounted by a parapet walkway. Excavation has indicated that defensive bastions were added to the Wall in the 3rd Century AD, and a number were also added during the medieval period when the Wall was repaired and refortified. By the mid-16th Century, however, with the continued expansion of London, its function as a town boundary and defence had ceased. London Wall survives in various states of preservation. Some parts of the Wall, especially along the eastern section, still stand to almost full height and the bastions are also clearly visible. Other parts are no longer visible above the present ground surface, but in these areas sections of the Wall survive as buried features, and sufficient evidence exists for their positions to be accurately identified for much of its length. The wall's role in the origins and history of England's capital city, its contribution towards an understanding of Romano-British and medieval urban development, and the light the remains throw on Roman and medieval civil engineering techniques, justify considering all sections of London Wall that exhibit significant archaeological remains as being worthy of protection.

Archaeological excavation has indicated that the buried remains of the fragment of the Roman Wall and the Roman, medieval and post-medieval gateway beneath Aldersgate Street survive well. They will provide valuable information on the construction techniques employed during both the Roman and medieval periods. The gateway is the only Roman one known on the Wall circuit which has been added to the Town Wall subsequent to the latter's construction, and thus provides evidence that additions were made to the Wall during the Roman period. Together with the remains of the medieval and later gateway, it will also contribute towards our understanding of the development of a major routeway into the city and its defences from Roman times through to the post-medieval period.

Details

The monument is situated beneath Aldersgate Street and number 10 Noble Street (the former site of Aldercastle House) and includes the buried remains of part of London Wall, the Roman and medieval defences of London, and the city gate of Aldersgate. London Wall was constructed towards the end of the 2nd century AD enclosing a semi-circular area of approximately 133ha on the north side of the Thames, from the site of Tower Hill in the east, to Blackfriars in the west. For much of its length the defences were strengthened by a berm and ditch, and gateways were built at principal points of entry. The Wall was reinforced and repaired throughout the Roman and medieval periods, and bastions were added. Excavation has indicated that during the later Roman period a riverside wall was constructed parallel to the north bank of the Thames in order to protect the southern part of London. The expansion of the city towards the end of the medieval period led to the decline of London Wall as a defensive feature. The monument includes a fragment of Roman walling to the east of Aldersgate Street, approximately 7m in length (which represents part of the north western side of the London Wall circuit) as well the remains of the Roman, medieval and post-medieval gateway of Aldersgate. The scheduling also includes elements of the pre-wall Roman city ditch, the Roman city wall ditch, the internal rampart and the medieval city ditch. Excavation has shown that the Wall stands on a foundation trench filled with puddled clay and flint, capped by a layer of rubble, and rises from an external sandstone plinth. The Wall itself has a rubble and mortar core and is faced with squared blocks of Kentish ragstone banded at intervals by tile courses. An excavation at the site by A Oswald in 1939, located in the centre of Aldersgate Street, uncovered a mass of ragstone masonry which projected northwards beyond the line of the Town Wall and represented part of the western tower of the Roman Aldersgate gateway. It had been roughly keyed into the fabric of the Wall and also overlay the Wall footings. It is thus considered to be a later, Roman insertion which postdates the construction of the Town Wall. Excavations at other gateways on London Wall, as well as at the site itself, provide evidence for the Roman ground-plan of this gateway, which will survive as a buried feature. It has a double carriage way, separated by a central spine, and flanked by two D-shaped projecting guard towers. Part of the medieval gateway was uncovered in 1922-3 by A Clapham, when the remains of a 15th century barbican with a polygonal tower at its north eastern angle were located. This gateway was rebuilt in 1617 when square projecting towers and pedestrian footways were erected either side of the carriageway. It was repaired following damage caused by the Fire of London in 1666, but was finally demolished in 1761. The medieval and later gateway appear to have been located on the site of the western half of the Roman gateway. Further archaeological excavation on the former Aldercastle House site (Now 10 Noble Street) in 1997-9 located the west-east wall running north of, and parallel to, the southern property boundary. In addition, to the north of the monument were found the traces of a north-south Roman road which, if projected on the same line, would have crossed the monument and passed through the conjectured position of the Roman east gate. A complex sequence of city ditches, from the 1st to 17th centuries, were also located within the monument boundary. Further sections of London Wall are known to survive approximately 21m to the west and 31m to the east of the monument and are the subject of separate schedulings. The surfaces of the road and pavements as well as No 10 Noble Street are excluded from the scheduling, although the ground beneath these features is included.

MAP EXTRACT The site of the monument is shown on the attached map extract.

Legacy

The contents of this record have been generated from a legacy data system.

Legacy System number:

26330

Legacy System:

RSM

Sources

Books and journals
Merrifield, R, The Roman City of London, (1957), 101-4,
Merrifield, R, The Roman City of London, (1965), 101-4,
Merrifield, R, The Roman City of London, (1965)
Schofield, J, Maloney, C (Eds), Archaeology in the City of London, 1907-1991: a guide..., ()
Schofield, J, Maloney, C (Eds), Archaeology in the City of London, 1907-1991: a guide..., (), 31
Lyon, J, Cripplegate Fort EC2, City of London: an assessement of archaeol, (2003)
Butler, J, Transactions of the London & Middlesex Archaeological Society in The City Defences at Aldersgate, (2001)
Butler, J, Transactions of the London & Middlesex Archaeological Society in The City Defences at Aldersgate, (2001), 41-111
Fox, G E, Archaeologia in Notes on a Recent Discovery of Part of the Roman Wall of London, (1889), 609-16
Fox, G E, Archaeologia in Notes on a Recent Discovery of Part of the Roman Wall of London, (1889)

Other
Harding, C, City of London survey of the scheduled sections of Roman , 1984,
Harding, C, City of London survey of the scheduled sections of Roman , 1984,
Grainger, I, A watching brief on the Scheduled Ancient Monument of Aldersgate, (1992)
Grainger, I, A watching brief on the Scheduled Ancient Monument of Aldersgate, (1992)

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