Moat Farm Dyke: a northern extension of Lexden Dyke; part of the Iron Age territorial oppidum and Romano-British town of Camulodunum

Reasons for Designation

The Latin term `oppidum' usually refers to a town, although in the context of the Roman invasions of Britain, its use in the writings of Julius Caesar and Suetonius encompassed a wider range of fortified settlements and native strongholds. In archaeological terminology `territorial oppida' is used to describe a settlement phenomenon of the later Iron Age - areas of farmsteads, field systems and nucleated settlements of various kinds covering wide areas bounded by substantial earthworks. Such sites are considered to have been tribal capitals or focal places for communities between the 1st century BC and the 1st century AD, serving as centres of trade, manufacture and social prominence. Only a handful of sites in England have been identified under this term (principally Colchester, Bagendon, Silchester, St Albans, Chichester, Grims Ditch and Stanwick), all of which lie in southern, central and western parts of the country. They all share the common characteristic of boundaries defined by massive linear banks and ditches, sometimes intermittent and positioned to include natural barriers such as rivers and marshes. The enclosed areas vary from between 30 sq km and 90 sq km, some marked out by curvilinear boundaries, others by more rectilinear patterns. Activities within the enclosed areas may vary considerably and, given that Iron Age society in southern England was not homogeneous, there is no reason to suppose that all territorial oppida exhibited the same status or served identical purposes. In addition to farmsteads, areas of nucleated settlement and related field systems, other known features of the enclosures include storage pits and wells, areas set aside for burials (sometimes extremely elaborate), temple complexes and areas of pottery manufacture, metal working and the minting of coins. Some, particularly those positioned in coastal or estuarine locations, provide evidence of widespread trade in the form of imported goods, notably Gallo-Belgic pottery, from the continental mainland and the western Roman Empire. Territorial oppida reflect the development of complex social organisation and increased permanence of settlement in the late Iron Age. They also provide some of the most valuable evidence for the impact of Roman conquest and government on native society. Given the rarity of this settlement form and its importance for our understanding of the period, all territorial oppida are viewed as being of national, if not international importance, and all surviving elements are considered worthy of protection.

The territorial oppidum surrounding Colchester (`Camulodunum' in antiquity) encompassed an area of about 25 sq km mainly located between the converging courses of the River Colne and the Roman River to the west of the Colne estuary. In addition to the rivers the settlement was defined and protected by the largest group of linear earthworks of the period in Britain. These developed over a period of about one hundred years from the foundation of the settlement in the early first century BC and mostly take the form of large V-shaped ditches with banks constructed from upcast on the sides facing the settled area. The dykes may have been made still more formidable by the addition of timber palisades and gateways, and they have been interpreted as an expression of the settlement's status, as a means to control and protect grazing stock and as an effective defence against chariots - one of the principal features of later Iron Age warfare. If placed end to end the dykes would extend over a total distance of about 25km. Some 6km now survive as extant earthworks, and many other sections are known to survive as buried features.

The interior of the oppidum is thought to have been largely agricultural - a mixture of enclosed fields, pasture and woodland - with small occupation sites scattered throughout and two particularly large and complex areas of activity located to the west and to the north. At Gosbecks, to the west, an extensive farmstead has been identified. This has been associated with Cunobelin (one of the most famous British kings prior to the Roman Conquest) and interpreted as a centre of political authority and religious practice. Further north, at Sheepen, excavations in the 1930s and 1970 revealed widespread evidence of industrial processes, the minting of coins and continental trade. Associated with the settlement sites are burial grounds, the most prominent of which are the Lexden Tumulus, Lexden Mount, a group of excavated burial enclosures at Stanway (beyond the western dykes) and a similar (unexcavated) enclosure at Gosbecks. These sites reflect the beliefs and complex burial rituals afforded to the the society's elite; a large number of less elaborate burials have been discovered across the oppidum.

The rulers and occupants may have fluctuated according to the relative fortunes of two rival tribal polities - the Trinovantes centred on modern Essex and the Catuvellauni based in modern Hertfordshire. An alternative suggestion is that the oppidum served as a Catuvellaunian colony within Trinovantian territory, maintained through political agreements or the warlike ascendancy of the former in order to provide this otherwise landlocked tribe with access to coastal trade. In either case, the oppidum was clearly of central importance to the region in AD 43 when it formed the primary military objective for the invading Roman army. After the collapse of local resistance, the Emperor Claudius personally led his victorious forces into the oppidum, which was subsequently reorganised to provide a centre of provincial government and bridgehead for the further conquest of Britain. A small Roman fort was constructed within the Gosbecks complex, and a larger legionary fortress was established on the hill to the east (now the centre of modern Colchester). As the focus of military activity shifted towards the north and west of Britain the fortress was redesignated as a `colonia', a chartered town for a colony of retired soldiers. `Colonia Victricensis' (City of Victory) was the first Roman town established in Britain and thus the earliest truly urban settlement in the country. The burgeoning town was destroyed in AD 60-61 - the first major casualty of the tribal revolt led by Boudicca, queen of the Iceni. In the aftermath of the revolt the town was rebuilt with a protective wall (based on the perimeter of the earlier fortress), and with the return of order the colonia developed in a manner apparently calculated to integrate the old and new social orders. Native settlement and burial practices continued within the territorial oppidum (now probably a `civitas' or self governing town) which was protected with additional dykes. A temple and a theatre were constructed at the Gosbecks site and the Sheepen industrial zone was maintained, enlarged and extended to include a further religious complex.

The collapse of Roman government in the early fifth century signalled the end of Colonia Victricensis. Medieval Colchester emerged within the walls of the former Roman town leaving the greater part of the extended settlement and oppidum to disappear beneath its rural hinterland. As a consequence the archaeological remains in this area are remarkable for the lack of later disturbance and present a unique opportunity for the study of the Iron Age and Roman past.

Moat Farm Dyke is one of the best surviving examples amongst the linear earthworks which defined the perimeter of the Iron Age settlement. The bank is a substantial and impressive earthwork which will contain valuable archaeological evidence for the date and manner of its construction. The attendant ditch also survives well as a visible and partly buried feature. The lower fills of the ditch are unlikely to have been disturbed and will similarly contain valuable evidence for the date when this section was built and the period over which it was maintained. The silts in the ditch may also contain environmental evidence illustrating the appearance of the landscape in which the dyke was set.

Together with its continuation to the south (Lexden Dyke), Moat Farm Dyke forms the westernmost boundary of the late Iron Age territorial oppidum, later to become one of the inner boundaries within an enlarged system constructed to define and defend the Roman colony and Romano-British civitas. It therefore forms part of the archaeological evidence for the development of one of the earliest `proto-urban' settlements in Britain and for its translation into Britain's first true town in the years following the Roman conquest.

Details

The monument includes the visible and buried remains of the northern part of a late Iron Age linear boundary earthwork (Lexden Dyke) located some 2km ENE of Colchester town centre, and lies within two areas of protection.

The section of dyke follows a NNE-SSW alignment for approximately 1.25km to the north of the River Colne. The southern end of Moat Farm Dyke is located at the junction of Baker's Lane and The Chase Way, some 200m north of the river. From this point northwards to Moat Farm (after which the dyke is named) the bank stands up to 1.5m high and 11m wide and the ditch (to the west of the bank) is 10m wide and 1m deep. The bank has been slighted along the western margin of the farm, and the ditch partly recut as a drainage channel. However, the bank reappears to the south of the railway cutting which bisects the centre of the dyke.

To the north of the railway cutting and within the second area of protection, both the bank and ditch continue within a wooded corridor for 250m. Beyond this point the ditch survives as a buried feature, accompanied by the bank which continues northward towards a bend in Baker's Lane, immediately south of its junction with Braiswick Road.

Moat Farm Dyke is similar in design to the Lexden Dyke which follows the same alignment to the south, beyond the Colchester bypass and across Lexden Park. The two dykes are believed to represent a single boundary, originally broken only by the River Colne and its flanking marshes.

The Lexden/Moat Farm Dyke is thought to be the third boundary constructed during the development of the oppidum of Camulodunum, added to the north of Heath Farm Dyke in the period 25-10 BC to provide a single barrier between the Roman River and the Colne. The boundary would have thus secured the approaches to the high status burial ground at Lexden (to the west of modern Colchester) and the industrial zone at Sheepen (to the north west).

The outbuildings alongside No 14 Baker's Lane and all fences and fence posts 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:

29461

Legacy System:

RSM

Sources

Books and journals
Brookes, H, The Earthworks around Colchester, (1972)
Hawkes, C F C, Crummy, P, Colchester Archaeological Reports in Camulodunum II, Vol. 11, (1995)

Other
Title: TL 9725-9726 Source Date: 1953 Author: Publisher: Surveyor: Antiquity Model 1:2,500
Radford, D and Gascoigne, A, The Colchester Iron Age Dykes: Archaeological summary, 1997, Colchester Museums Internal Report
RCHME, Monuments of North-East Essex, (1922)

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