Hertfordshire Grim's Ditch: 210m long section immediately north west of Woodcock Hill

Reasons for Designation

Linear boundaries are substantial earthwork features comprising single or multiple ditches and banks which may extend over distances varying between less than 1km to over 10km. They survive as earthworks or as linear features visible as cropmarks on aerial photographs or as a combination of both. The evidence of excavation and study of associated monuments demonstrate that their construction spans the millennium from the Middle Bronze Age, although they may have been reused later. The scale of many linear boundaries has been taken to indicate that they were constructed by large social groups and were used to mark important boundaries in the landscape; their impressive scale displaying the corporate prestige of their builders. They would have been powerful symbols, often with religious associations, used to define and order the territorial holdings of those groups who constructed them. Linear earthworks are of considerable importance for the analysis of settlement and land use in the Bronze Age; all well- preserved examples will normally merit statutory protection.

The boundary known as the Buckinghamshire and Hertfordshire Grim's Ditch includes numerous surviving sections from within three main linear earthworks aligned along the Chiltern Hills between Bradenham and Berkhamsted, spanning a total distance of 18km. It does not appear that these principal sections were ever joined to form a continuous boundary. Current evidence suggests that the sometimes quite sizeable gaps represent areas which were formerly forested or in which natural features served to perpetuate a division of the land. The same pattern has been discerned along the North Oxfordshire Grim's Ditch, to the west of the Thames. A further comparable linear boundary, the Moel Ditch, extends tot he east across parts of neighbouring Bedfordshire. For the most part the visible sections of Grim's Ditch in the Chilterns include a wide single ditch flanked by a bank of upcast earth, which is always upslope of the ditch. Other features, discovered by limited excavations include a turf core within the bank, a berm separating bank and ditch (concealed over time by the spread of bank material) and a trench for a fence or palisade, along the outer rim of the ditch. The Buckinghamshire and Hertfordshire Grim's Ditch is thought to have served as a territorial boundary, separating, and perhaps enclosing, organised groups of land and settlement. It may also have been an agricultural boundary, denoting grazing areas and impeding the movement (or theft) of stock. Excavations to date have provided only limited dating evidence. Pottery recovered from the fill of the ditch indicates that it was in existence in the Iron Age. As such the boundary provides important evidence for the management of the landscape in the centuries preceding the Roman Conquest in AD 43, although it may have a considerably earlier origin. It remained a notable feature in later centuries, acquiring its present name (a variation on the name of the god, Odin) at some point in the early medieval period, perhaps during the period of pagan Saxon settlement in the 5th and 6th centuries. The earliest recorded use of the term 'Grim's Ditch' occurs in a charter granted by Edward, Earl of Cornwall in 1291. All sections of the Buckinghamshire and Hertfordshire Grim's Ditch which survive in visible form, or as well-preserved buried remains (identified by aerial photography or ground survey), are considered integral to a general understanding of the monument and will normally merit statutory protection. This section of Grim's Ditch immediately north west of Woodcock Hill survives well as a visible earthwork along most of its length and provides a fascinating insight into the nature of early territorial land division in the Chiltern Hills. It will contain archaeological evidence for the manner of its construction as well as environmental evidence for the appearance of the landscape in which it was built. The archaeological evidence may also include artefacts or scientific dating material from which to determine the period of its construction and the duration of its maintenance as an active boundary.

Details

The monument includes a 210m long section of a prehistoric boundary known as the Hertfordshire Grim's Ditch running broadly north west to south east between Bell Lane and the grounds of Woodcock Hill, a large Victorian house on Durrant's Lane. This section of Grim's Ditch is located on high ground in former parkland associated with Woodcock Hill overlooking Northchurch and the Bulbourne Valley to the north. The boundary survives as a clearly visible bank and ditch along most of its length. The earthen bank measures up to 12m wide and stands up to 0.5m high in some places. To the south of the bank lies a parallel ditch, approximately 12m wide and up to 0.4m in depth. An excavation carried out in 1973 across Grim's Ditch in the parish of Tring, approximately 5km to the west, produced evidence of a level area, or berm, separating the bank and ditch. Evidence for a palisade trench, which would have supported a wooden fence, was also found along the outer edge of the ditch. Similar components also survive as buried features along this section of Grim's Ditch. A further excavation, also carried out in 1973, immediately to the west of this section produced pottery believed to be Iron Age in date. A further section of Grim's Ditch exists 1.4km to the west in Hamberlins Wood. This section, and others along the entire known route of the ancient boundary are the subject of seperate schedulings. All fences are excluded from the scheduling, although the ground beneath them is included.

MAP EXTRACT The site of the monument is shown on the attached map extract. It includes a 2 metre boundary around the archaeological features, considered to be essential for the monument's support and preservation.

Legacy

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

Legacy System number:

35349

Legacy System:

RSM

Sources

Books and journals
Network Archaeology, , Grim's Ditch: Archaeological and Management Survey Phase III, (1999)
Davis, J, Records of Buckinghamshire in Grim's Ditch In Buckinghamshire And Hertfordshire, Vol. 23, (1981), 23

End of official list entry

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