The monument includes the visible and buried remains of the central section of a late Iron Age linear boundary earthwork known as Lexden Dyke Middle, which is located to the south of Lexden Road, some 2km east of Colchester town centre. Lexden Dyke Middle covers a total distance of about 1km, extending southwards along the eastern side of Lexden Park for approximately 400m, before turning to the SSE and continuing through Bluebottle Give to the rear of Magazine Farm Way. At the northern end the dyke follows the upper scarp along the eastern side of a natural valley which runs north to south through Lexden Park and the adjacent gardens of properties to the east. The bank is largely absent for the first 200m length to the south of Lexden Road, although excavations in 1932 revealed the surviving base of this earthwork and demonstrated that the original construction was probably slighted after the Roman conquest. The natural scarp to the west was also shown to have been enhanced by increasing the severity of the slope and creating a counterscarp ditch (now largely infilled) at the base. Part of the dyke was found to have overlain a child’s cremation buried in a shallow pit. This may reflect a ritual associated with the raising of the bank, or simply a matter of coincidence – the grave being an outlying component of an extensive Iron Age burial area known to exist on the eastern side of the dyke. A narrow break in the dyke at the southern end of the slighted section was shown in 1932 to have been an original entranceway. To the south of this point the bank rises to a height of 3m and continues, measuring up to 21m in width and accompanied by a substantial western ditch, towards the south eastern corner of Lexden Park. A trench was cut across the full width of the dyke in 1932 found the bank to be composed principally of gravel, supported on the west side by stacked turf which had been stripped from the original ground surface prior to construction. Evidence was also found for a timber revetment along the western face of the bank and for a retaining fence following the tail of the bank to the east. The ditch, measuring 13.4m across and 4.3m deep, was originally cut to a v-shaped profile, with a further narrow gully incised along the base. The bank has been levelled at the south eastern corner of the park, and the ditch infilled leaving no visible trace. The course of the buried ditch can, however, be determined from its reappearance on the south side of the footpath which separates Lexden Park from Bluebottle Grove, and the intervening section (through the garden of No 30 St Clare Road) is included in the scheduling. The dyke continues for a further 420m through Bluebottle Grove, a narrow wooded corridor between Magazine Farm Way and the grounds of the Philip Morant Secondary School. This section is in the care of the Secretary of State. The bank survives beneath a footpath on the eastern side of the ditch, maintaining a width of about 19m which extends, as a slight rise, into the adjacent school sports filed. The partly infilled ditch has a rounded base and measures some 14m across and 2.5m deep, although limited excavation in 1987 revealed an original v-shaped profile descending to 4.1 m, with evidnec of secondary work to steepen the lower portion. The bank, also examined in 1987, proved to survive to a height of 1.4m beneath the modern footpath. Evidence for revetment was not found, since the relationship between the bank and the ditch had been damaged during World War II, when the Bluebottle Grove section was adapted to form a tank trap. During this work, in 1943, the local archaeologist A F Hall noted that the southern end of the dyke converged and overlay the ditch of an earlier dyke (Heath Farm Dyke) which is now known to extend around the Iron Age settlement at Gosbecks to the south. A third boundary known as the Prettygate Dyke, also converged at the southern end of Bluebottle Grove. This dyke (together with the Straight Road or Triple Dyke) formed part of an enhanced pattern of western defences created shortly before the Roman invasion of AD 43. Following the Romans’ successful attack on the Colchester oppidum, these two dykes appear to have been modified to defence a temporary encampment based around the Lexden Springs, with the Lexden Dyke itself serving as the eastern boundary. Prettygate Dyke and the section of Heath Farm Dyke approaching Bluebottle Grove have been overlain by modern developments and are not included in the scheduling. The straight Road/Triple Dyke is the subject of a separate scheduling. Artifacts recovered during the 1932 excavations indicate that Lexden Dyke was constructed in the final years of the first century BC. A southerly extension to the dyke (Lexden Dyke South) has been traced by excavation, although its full extent is not known. This is now overlain by housing and is not included in the scheduling. To the north, the dyke continues beyond the break formed (since Roman times) by Lexden Road and leads towards the River Colne. This section, known as Lexden Dyke North, is scheduled as a separate monument. On the far bank of the river a similarly aligned dyke (the Moat Farm Dyke) extends in a north easterly direction for 1.5km. The Lexden and Moat Farm Dykes are believed to represent a single boundary, which was originally broken only by the River Colne and its flanking marshes. It is thought to be the third boundary constructed during the development of the oppidum of Camulodunum, added to the north of Heath Farm Dyke to provide a single barrier between the Roman River and the Colne, thus securing the western approaches to the intervening spur. In particular, the Lexden Dyke is considered to have provided a single barrier integrating the defences at two distinct settlement areas, one at Gosbecks to the south west of modern Colchester, the other to the north west at Sheepen. The modern surfaces of footpaths and all fences and fence pots are excluded from the scheduling, although the ground beneath these features is included. <1>