Cambridge motte and bailey castle, Civil War earthworks and the buried remains of an Iron Age defended settlement, Roman town and former county gaol

Summary

The monument comprises the earthwork and buried remains of Cambridge motte and bailey castle, first built in 1068, Civil War earthworks built by Oliver Cromwell in 1642, and the buried remains of an Iron Age defended settlement, Roman Town (1st century AD) and the former county gaol, built in the early 19th century, by George Byfield.

Reasons for Designation

The earthwork and buried remains of Cambridge Castle and Civil War earthworcks, the buried remains of an Iron Age defended settlement, Roman Town and former ounty gaol are scheduled for the following principal reasons.

Potential:

* for the earthwork and buried remains with potential to considerably enhance our understanding of the castle and the place it held in the wider landscape as well as the earlier and later occupation of the site as a strategic and defended settlement including during the Civil War.

Diversity:

* for the broad diversity of surviving features including the motte, buried archaeological deposits of the interior of the bailey and the outer ditch, the Civil War earthworks and the buried remains of settlements before and after the establishment of the castle.

Period:

* Motte and Bailey castles, Iron Age defended settlements and Roman Towns are all defining monument types of their periods, the Civil War earthworks are equally symbolic of military operations in the mid-C17;.

Documentation:

* on account of the extensive historical and archaeological documentation which demonstrates the evolution and development of the site from an Iron Age defended settlement to Roman Town, Medieval castle, Civil War defences and former county gaol and how the site has influenced the development of the city of Cambridge ever since.

Survival:

* as well-preserved earthworks and buried remains.

History

Motte and bailey castles are medieval fortifications introduced into Britain by the Normans. They comprised a large conical mound of earth or rubble, the motte, surmounted by a palisade and a stone or timber tower. In a majority of examples an embanked enclosure containing additional buildings, the bailey, adjoined the motte. Motte castles and motte-and-bailey castles acted as garrison forts during offensive military operations, as strongholds, and, in many cases, as aristocratic residences and as centres of local or royal administration. Built in towns, villages and open countryside, motte and bailey castles generally occupied strategic positions dominating their immediate locality and, as a result, are the most visually impressive monuments of the early post-Conquest period surviving in the modern landscape. Over 600 motte castles or motte-and-bailey castles are recorded nationally, with examples known from most regions. As one of a restricted range of recognised early post-Conquest monuments, they are particularly important for the study of Norman Britain and the development of the feudal system. Although many were occupied for only a short period of time, motte castles continued to be built and occupied from the C11 to the C13, after which they were superseded by other types of castle.

Cambridge motte and bailey castle occupies a position in the landscape that had long been recognised as a strategic location and although the castle is the most visible element of the site it has a long and distinguished history. A defended settlement is evident on the site from the late Iron Age, at which time the settlement was surrounded by a single ditch and embankment enclosing an area of over seven hectares. A large, defended gateway was added to the north of the area in the first century AD and in the second century, at the time of Emperor Hadrian, a small, planned town developed with evidence of small-scale industry and a religious centre. The town took advantage of the location, controlling access and movement across the River Cam located approximately 240m to the south-east. The defences were further reinforced by the Romans again in the C4 by building a stone wall around the town. The wall measured around 2.3m wide and 2.5m high with a 12m wide and 4m deep ditch in front. The site was abandoned with the fall of the Roman Empire in C5, but the walls remained until the C11.

The area inside the Roman walls was re-occupied by the mid-C10 in response to the Viking attack on Cambridge in AD875. Domesday Book, compiled in 1086 documents that by the time of the Norman conquest Cambridge was a thriving town and around 1068 William the Conqueror, facing a potentially rebellious population, built the motte and bailey castle, with a central mound and timber keep.

In 1283, Edward I rebuilt the castle in stone, the earth and timber ramparts were replaced with clunch foundations, Barnack stone curtain walls and towers and the timber keep was also replaced in stone. The castle comprised an enlarged keep, a high curtain wall, an outer barbican with drum towers on the corners. Within the bailey was a Great Hall, chapel and kitchens. The castle was complete by 1306 including a ‘Great Gate’ on the south-west side.

By 1441 the castle was again in decline. The Great Hall had no roof and stone was robbed from the curtain walls and towers to build King's College, although the Great Gate appears to have survived.

With the outbreak of the Civil War in 1642 Oliver Cromwell turned the castle into an artillery fortress. Close to what is now Chesterton Road the castle ditch was reused and three bastions were constructed. By December 1644 new ditches had been dug to the north and east, the fortress was complete although the fortification was never used in battle and was already in decline by 1647.

By the C18 the only surviving buildings were a Civil War barrack block and the medieval gatehouse. During the C17 and C18 many of the earthwork defences were levelled including the north-west Civil War bastion and the moat surrounding the central motte. Castle Street had been established in 1660-1680 but the C18 saw development of housing along Castle Street and the wider area was developed for housing in the C19.

In 1803, plans were drawn up for the construction of a new county gaol by George Byfield. This comprised a brick-built octagonal building, a governor’s house and an imposing gateway to the south-east of the gaol. In 1863, the gaol was extended to increase accommodation and the number of cells.

During the C18 and C19 the focus of the castle area changed from military to a civilian, administration and justice function.

In 1840-1842 the Great Gate was demolished to make way for the county courts known as Shire Hall or Shire House. The construction of the county courts required lowering the ground level by three metres and was considered to have removed all traces of the gatehouse although geophysical survey on the western side of the monument, beneath Castle Hill car park, has provided evidence to suggest archaeological remains do survive beneath the ground surface. Most of the castle site was occupied by the prison and courts but in 1928 the prison was purchased by Cambridge County Council and demolished to make way for the new County Hall built in 1931. Bricks from the county gaol were used in the construction. Footings of the prison can still be seen as crop marks in the lawn between Shire Hall and the castle mound.

During the Second World War, Cambridge was considered to be readily defensible in the event of German invasion and a series of anti-tank ditches were constructed around the city. The surviving Civil War embankments were reinforced with barbed wire and slit trenches were dug into the bastions. A company of the 5th Battalion Cambridgeshire Home Guard manned these defences, and further plans were drawn up in 1942 to defend the site.

After the war, the castle was again demilitarised, but the tensions of the Cold War again saw the castle in a defensive role. A control centre, in case of nuclear attack, was located below Shire Hall and subsequently moved to beneath Castle Court, to the north of the scheduled area.

The condensed history and evolution of this strategic location can be traced through detailed mapping from the C19 and C20. However, the ongoing development of this area of Cambridge has also allowed archaeologists to access the area with around 30 archaeological excavations having taken place over a series of nearly 30 years within the bounds of the former Roman Town.

Part of Castle Park had been used as a car park for Shire Hall since the 1960s and was partially excavated in 1983, but from 1984 to 1986 a total of 10,000 square meters of the site was excavated. Further opportunistic works were carried out around what is now Castle Park and all these works have added to the corpus of knowledge about Cambridge Castle, its predecessors and post-mediaeval occupation.

South of the castle mound, at the foot of the motte and including the moat, excavations in 1989 identified a ditch 10m wide and 4m deep, with a waterlogged base. This is thought to be the castle moat or part of the outer defences of the Cromwellian fortress or a combination of both. The line of the ditch at least in part lies in the gardens of properties south of the scheduled castle mound.

All sources and information are documented in, and available from, the extensive records in the Cambridgeshire Historic Environment Record (HER), with key reports listed in the sources below.

Details

PRINCIPAL ELEMENTS: the monument comprises the earthwork and buried remains of Cambridge motte and bailey castle, first built in 1068, Civil War earthworks built by Oliver Cromwell in 1642, and the buried remains of an Iron Age defended settlement, Roman Town (first century AD) and former county gaol, built in the early C19, by George Byfield.

DESCRIPTION: the monument is located in a prominent position in the landscape, on the end of a ridge of high ground marked by Huntingdon Road, just where the ridge ends before dropping into the Cam Valley. This stretch of the River Cam is one of the last crossable sections before it feeds into the fenlands. The high position and views over the crossing point and surrounding area has made this site attractive to human activity and occupation from later prehistory onwards.

The Medieval motte remains the most prominent feature, located at the southern end of the site, it survives as an earthwork approximately 12.5m high which, at its summit, measures 32.5m above Ordnance Datum (AOD). At its base it measures between 62 and 65m in diameter. Developments to the south, outside the scheduled area, have impacted the Castle remains particularly the construction of Castle Brae and other buildings. This is the area at the foot of the motte and includes the moat. In an attempt to create a more level area for both the house and associated garden, the Victorian builders dug into the castle mound and built a boundary wall. The pressure of the mound behind has caused the wall to lean considerably in places.

The civil war earthworks survive for a total length of just over 200m along the east side of the monument, taking in part of the north-east bastion, south-east bastion, the ramparts between and the connecting earthwork to the motte. The civil war earthworks stand on average 2m high from the ground level of the castle interior but are significantly higher at the northern end, in the area of the bastion and from the gardens backing on to the monument on the east and south sides. These earthworks have been compromised by more recent development, particularly the octagonal building adjacent to the northern end of the site. This building is known to have a basement and is likely to have destroyed or at least heavily degraded evidence of the defences in this area and is not therefore part of the scheduling.

Evidence of other periods of activity on the site survive as below ground remains and have been documented from the many archaeological excavations on the site. The foundations of the county gaol survive as buried features across the site and show as parchmarks on the lawn between the Shire Hall and the castle mound in dry summers and a geophysical survey has also been undertaken to map the location and survival of the buried remains.

Fortification ditches have been present on the site in at least three phases of its history. These are necessarily deep and wide, usually cutting into bedrock and are therefore very resistant to later damage and hold a strong archaeological potential to retain important deposits, some of which may be waterlogged and therefore perfect contexts for the preservation of organic remains.

The depth and complexity of the archaeological remains of the site has been repeatedly demonstrated through excavations in the area. These have shown that in between areas of disturbance deeply stratified remains do survive with potential to add to our knowledge and understanding of the evolution, continuity and change in the use of this nationally important site over at least the last 2000 years.

EXTENT OF MAPPING: the mapped depiction includes the earthwork and buried remains of the castle, the Civil War earthworks and areas of the Iron Age defended settlement, Roman town and former county gaol which survive within the constraint area.

EXCLUSIONS: all road, path and parking surfaces, signage, parking pay machines, drain covers, fences and street lighting are excluded from the scheduling although the ground beneath is included.

Legacy

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

Legacy System number:

CB 14

Legacy System:

RSM - OCN

Sources

Books and journals
Cressford, C, Proceedings of the Cambridge Antiquarian Society, (1972), 137-147
Alexander, J, Pullinger, J, Roman Cambridge, Excavations on Castle Hill in Proceedings of the Cambridge Antiquarian Socierty , Vol. LXXXVIII, (1999), ?
Osbourne, M, Cromwellian Fortifications in Cambridgeshire, (1990), all
Taylor, A, Cambridge, The Hidden History, (2004)

Other
Cambridge City Council. Castle and Victoria Road Conservation Area Appraisal 2012
The History, Evolution, Changes of Use and Current Condition of the Historic Asset: Castle Park, Cambridge. 2013 Quinton Caroll
Castle Mound Investigation Non- intrusive study. Atkins 2009
Cambridgeshire County Council Historic Environmanet Record - multiple entries and sources
Castle and Victoria Road Conservation Area Appraisal 2013
Local Plan 2018 Cambridge City Council

End of official list entry

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