Buckinghamshire Grim's Ditch: 875m long section between Leylands Farm and Shire Lane

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 and spanning a total distance of 18km. It does not appear that these principle 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 to the 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 territoral boundary separating, and perhaps enclosing, organised parcels of land and settlement. It may also have been used as 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 for the management of the landscape in the centuries proceding 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' occurrs 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 photographs or ground survey), are considered integral to a general understanding of the monument and will normally merit statutory protection. The section of Grim's Ditch between Leyland's Farm and Shire Lane survives well as a visible and partly buried earthwork along much of its length. 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. This section represents part of a larger stretch of Grim's Ditch extending between Wendover and Berkhamstead which follows an arc across high ground above the Aylesbury Vale and the Bulbourne Valley. Prehistoric hillforts are located close by: on Boddington Hill on the north west side of Grim's Ditch and at Cholesbury to the south.

Details

The monument includes a 875m long section of a prehistoric boundary known as the Buckinghamshire Grim's Ditch, running broadly south west to north east between Bottom Road and Shire Lane. It is situated on high ground following a similar course to the modern Ridgeway path less than one kilometre to the north, which is itself a reflection of a prehistoric route along the line of the Chiltern Hills. This section of Grim's Ditch, between Leylands Farm and Shire Lane, is marked by the visible remains of the bank along most of its length. The earthen bank measures up to 11m wide and over 1m high in some places. The ditch lies parallel to the south east side of the bank, visible as a shallow depression to the north east, near Shire Lane, where it measures 12m wide and 0.8m deep, but otherwise now largely buried by accumulated soil and silt. An excavation, carried out in 1973 along a section of Grim's Ditch approximately 350m to the north east 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 may also survive as buried features along this section of Grim's Ditch. Further sections of Grim's Ditch exist to the south west around Lanes End, and to the north east beyond Longcroft. These sections and others along the entire known route of the boundary are the subject of separate schedulings. Concrete hard standings in some of the fields overlie small areas of the monument and much of the ditch is overlain by a private driveway. These modern surfaces are excluded from the scheduling together with all gates, stiles and fences, 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:

35344

Legacy System:

RSM

Sources

Books and journals
Network Archaeology, , Grim's Ditch: Archaeological and Management Survey Phase III, (1999)

End of official list entry

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