Grim’s Ditch

It is far from grim when scattered with bluebells in the spring, but many people will know a part of The Ridgeway near Wallingford, Oxfordshire, as ‘Grim’s Ditch’. It is a memorable and favourite place for many visitors and, with a high bank and a ditch more than three metres deep in some places, it is a striking example of an ancient linear earthwork. Grim’s Ditch is a name the Anglo-Saxons gave the feature and derives from the Norse word Grimr meaning Devil and a nickname for Odin or Wodin the God of War and Magic. It is thought the Anglo-Saxons used ‘Grimr’ to refer to features they couldn’t explain or found mysterious i.e. they didn’t create them. Read on below….

Banner image: Bluebells along Grim’s Ditch near Mongewell, Oxfordshire. Credit: Wormholealien, Wikicommons

Grim’s Ditch was deeper and the bank higher when it was first dug out. It may date back as far as the Bronze Age (1000 BC) but the stretch near Wallingford is most likely to date from the late Iron Age, perhaps around 100 BC. Originally, it would have been clear of trees and scrub and so it would have been visible from miles around, especially with the freshly dug white chalk reflecting the sunlight and moonlight.

There are numerous Grim’s Ditches, Grym’s Dykes etc across the countryside but it cannot be assumed they are connected or similar in any way other than name. Looking further out along the Trail, several other linear earthworks near The Ridgeway can be seen on maps labelled Grim’s Ditch and, if they were part of a connected system, they represent a huge land division extending for miles over the Chilterns and North Wessex Downs.

For example, some miles to the north of Wallingford, The Ridgeway follows another substantial section of Grim’s Ditch near Pitstone in Buckinghamshire. It is hidden for much of its length in woodland. Other sections run parallel to the Trail near Tring Park in Hertfordshire, near Princes Risborough in Buckinghamshire and between Harwell and the Wantage Monument in Oxfordshire. This last stretch is a clear example of how earthworks are vulnerable to land use change because sections were ploughed away some years ago.

More recently, Historic England flagged concerns about the stretch of Grim’s Ditch near Wallingford and it was placed on the ‘Heritage At Risk Register’. A survey of the earthwork in 2021 found it was suffering damage from badger tunnelling, wind-blown trees and gradual erosion where people are concentrated onto a narrow path. To protect and conserve Grim’s Ditch, the National Trail Team are working with landowners, Historic England, county archaeologists, volunteers and others on a new project launched in 2023 – the Historic Ridgeway Project.

Notes: More information about other archaeological features along The Ridgeway such as hillforts is available in other Top 50 entries (not all Top 50 entries will be available until end of December 2023).

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