Grim's Ditch (Chilterns)

Pottery shards have been unearthed in excavations during the 1970s and 1980s suggesting that its origin may have been during the Iron Age and was believed to have been during a period when the landscape was clearer of scrub and the dense woodland than today as the straighter sections would have required clear lines of sight.

The Anglo Saxons commonly named features of unexplained or mysterious origin Grim.

It is thought by the Ordnance Survey (1974) that it may be a set of local boundaries used to control the movement of cattle and carts and dating back to the Iron Age, as no Anglo-Saxon event is connected with it.

[1] Download coordinates as: In July 2024, Buckinghamshire Council announced that it had given consent for approximately 75 metres (246 ft) of the earthworks near Great Missenden to be excavated as part of the construction works for the High Speed 2 railway line.

A spokesman stated that the council "bitterly regret that damage will be done to any part of this ancient monument".