Devil's Dyke

Devil’s Dyke is a long earthen bank and ditch running for eleven kilometres across the chalk uplands of south Cambridgeshire and into Suffolk. It stands ten metres high in places, with a deep ditch on its southwest side facing the flat marshy fens to the north and the former woodlands to the south. The dyke is one of several ancient linear earthworks built to control movement along old trackways such as the Icknield Way. It is protected as a Scheduled Monument and forms part of a Special Area of Conservation. Historians believe the dyke was raised by Anglo-Saxon settlers to block a narrow land bridge between the fens and the woods. The Anglo-Saxon Chronicle mentions Edward the Elder fighting the Danes ‘between the Dyke and the Ouse’ in 905. Excavations in 1923 found Roman objects beneath the bank, showing it was built after Roman times. Similar dykes nearby include Fleam Dyke, where radiocarbon dating suggests a date between AD 330 and 510. The dyke once formed a formidable barrier but fell out of use soon after it was made. Today the dyke crosses farmland, racecourse edges and private woodlands near Woodditton. Its chalk grassland supports rare plants such as purple milk-vetch and pasque flower. The site also includes areas of chalk scrub and woodland, providing habitats for diverse wildlife. Visitors can walk along the old earthwork and look across the open landscape where the fens meet the higher ground. The dyke’s broad banks and deep ditches remain clearly visible, marking out the ancient boundary.