|Site of Special Scientific Interest|
|Grid reference||TL 612 619 |
|Area||98 acres (39.8 hectares) |
|Location map||Magic Map|
Devil's Dyke or Devil's Ditch is a linear earthen barrier, thought to be of Anglo-Saxon origin, in eastern Cambridgeshire and Suffolk. It runs for 11 kilometres (6.8 mi) in an almost straight line from Reach to Woodditton, with a 10-metre-high (33 ft) ditch and bank system facing southwestwards, blocking the open chalkland between the marshy fens to the north and the formerly wooded hills to the south.   It is a Scheduled Monument, a biological Site of Special Scientific Interest and a Special Area of Conservation.
The name Devil's Ditch or Dyke is a post-medieval one. In medieval times it was simply called the dic ("the ditch"), or le Micheldyche or magnum fossatum ("great ditch"). 
Devil's Dyke is over 7 miles (11 km) long and is the largest of a series of ancient dykes in Cambridgeshire. In some places the bank measures 9 metres (30 ft) high and 36.5 metres (120 ft) across. The highest point along the Devil's Dyke is at Gallows Hill, where it measures 10.5 metres (34 ft) from the bottom of the ditch to the top of the earth wall.
Since the 19th century, a railway line and roads have been cut through the dyke, including the combined A14 and A11 roads, and a branch line of the Ipswich to Ely rail line.
From Reach, the dyke crosses farmland, before running along the edge of the July Course at Newmarket Racecourse and then through the woods of a private estate near the village of Woodditton.  The Rowley Mile course is unusual in that it can have races which start in one county, Cambridgeshire, and finish in another, Suffolk. It crosses the Devil's Dyke where it has been previously levelled.
There have been a number of excavations and investigations of the dyke in modern times, notably in 1923, 1988 and 1991. Excavations in 1923/24 of a stretch of dyke close to a Roman house yielded Roman artefacts under the dyke, indicating a post-Roman construction date. The results of a 1988 electrical resistance survey of the point where the ancient Street Way cuts through the dyke were inconclusive. In 1991, little was found when a small part of the dyke (measuring 8 × 3 metres (26.2 × 9.8 ft)) was excavated prior to the construction of a new aqueduct. The Dyke is thought most likely to be Anglo-Saxon, by analogy to the similar Fleam Dyke for which radiocarbon dating was performed in the 1990s, with Fleam Dyke's earliest construction phase dated within the uncertainty range of AD 330 –510.  The site is a Scheduled Monument. 
The earthwork has been described by various different commentators since Anglo-Saxon times. The Anglo-Saxon Chronicle may refer to the Devil's Dyke in its annal for 905, when Edward the Elder is recorded as fighting and defeating the Danes of East Anglia, after first laying waste to the countryside: 'and he laid waste their land between the Dyke and the Ouse as far northward as the Fens'—' and oferhergade call hera land betwuh dicun and Wusan. call oþ da fennas norð' .  Abbo of Fleury, writing in the late 10th century, described East Anglia as "fortified in the front with a bank or rampier like unto a huge wall, and with a trench or ditch below in the ground".  The mediaeval Flores Historiarum , referred to "...duo fossata sancti Eadmundi..." – the two fortifications of St Edmund – when describing the battle between Edward and his adversaries. 
Devil's Dyke is the largest of several earthworks in south Cambridgeshire that were either boundary markers or designed to control movement along the ancient trackways of Street Way (Ashwell Street) and Icknield Way. When it was created, it completely blocked a narrow land corridor between the southern edge of a region of water-logged marsh (now known as The Fens) in the north-west and dense woodlands in the south, so making circumvention difficult and forming an effective defensive barrier for the lands to the east. The dyke may have served as a way of controlling trade and movement in and out of the area. Findings such as the small quantity of silt in the ditch fills suggest that the dyke fell into disuse soon after it was built.
The other Cambridgeshire dykes include Fleam Dyke, Brent Ditch and Bran Ditch. In Suffolk, to the north west of Bury St Edmunds, a fifth earthwork, Black Ditches, Cavenham, guards the Icknield Way.
The site has extensive chalk grassland with diverse species, and areas of woodland and chalk scrub. Rare plants, such as purple milk-vetch, bastard toadflax and pasque flowers, have been recorded.  The site is a 98-acre (39.8 hectare) biological Site of Special Scientific Interest and a Special Area of Conservation. 
The American–British author Bill Bryson describes a walk along Devil's Dyke Notes From a Small Island (1995),  describing the dyke to be only 1300 years old, which was the scholarly consensus prior to radiocarbon dating of the similar Fleam Dyke, published in 1997. 
Cambridgeshire is a ceremonial and non-metropolitan county in the East of England government statistical region, and popularly known as one of the three counties of East Anglia. The largest city is Peterborough, followed by the county town of Cambridge. In 1974, modern Cambridgeshire was created through the amalgamation of Cambridgeshire and Isle of Ely with Huntingdon and Peterborough, which including the historic counties of Huntingdonshire and the Soke of Peterborough. A majority of the county is locally governed by Cambridgeshire County Council in combination with the lower tier non-metropolitan district councils of Cambridge, East Cambridgeshire, Fenland, Huntingdonshire, and South Cambridgeshire. Peterborough however is governed as a unitary authority with one council, Peterborough City Council. It is bordered by Lincolnshire to the north, Norfolk to the north-east, Suffolk to the east, Essex and Hertfordshire to the south, and Bedfordshire and Northamptonshire to the west.
Burwell is a village and civil parish in Cambridgeshire, England, some 10 miles north-east of Cambridge. It lies on the south-east edge of the Fens. Westward drainage is improved by Cambridgeshire lodes (waterways), including Burwell Lode, a growth factor in the village. A population of 6,309 in the 2011 census was put at 6,417 in 2019.
Wansdyke is a series of early medieval defensive linear earthworks in the West Country of England, consisting of a ditch and a running embankment from the ditch spoil, with the ditching facing north.
Grim's Ditch, Grim's Dyke or Grim's Bank is a name shared by a number of prehistoric bank and ditch linear earthworks across England. They are of different dates and may have had different functions.
Fen Ditton is a village on the northeast edge of Cambridge in Cambridgeshire, England. The parish covers an area of 5.99 square kilometres (2 sq mi).
Stow cum Quy, commonly referred to as Quy, is a village and civil parish in Cambridgeshire, England. Situated around 4 miles (6.4 km) north east of Cambridge lying between the Burwell Road (B1102) and the medieval Cambridge to Newmarket road, it covers an area of 764 hectares.
The A505 is a road in the East of England. It follows part of the route of the Icknield Way and the corresponding Icknield Way Path and runs from Leighton Buzzard in Bedfordshire to the A11 Abington Interchange North in Cambridgeshire.
Fleam Dyke is a linear earthwork between Fulbourn and Balsham in Cambridgeshire, initiated at some timepoint between AD 330 and AD 510. It is three miles long and seven metres high from ditch to bank, and its ditch faces westwards, implying invading Saxons as its architects. Later, it formed a boundary of the Anglo-Saxon administrative division of Flendish Hundred. At a prominent point, the earthwork runs beside Mutlow Hill, crowned by a 4000-year-old Bronze Age burial mound.
Wuffa is recorded in the Anglo-Saxon genealogies as an early king of East Anglia. If historical, he would have flourished in the 6th century.
Stetchworth is a small village and civil parish in East Cambridgeshire, England, 3 miles (5 km) to the south of the horse-racing centre of Newmarket and around 12 miles (19 km) east of Cambridge.
Icklingham is a village and civil parish in the West Suffolk district of Suffolk in eastern England. It is located about 7 miles (11 km) north-west of Bury St Edmunds, 4 miles (6.4 km) south-east of Mildenhall and 9 miles (14 km) south-west of Thetford in Norfolk. The village is on the A1101 road between Bury St Edmunds and Mildenhall in the north-west of the county. The area around the village, characterised by a sandy gravel-laden soil, is known as Breckland, though an arm of the fen-like peat follows the River Lark past the village.
Cavenham is a village and civil parish in Suffolk, England, 10 kilometres (6 mi) northwest of Bury St Edmunds. It is in the local government district of West Suffolk, and the electoral ward of Icini. At the 2001 UK census, Cavenham Parish had a population of 127. In the 1870s it had a population of 229.
Bran Ditch or Heydon Ditch is generally assumed to be an Anglo-Saxon earthwork in southern Cambridgeshire, England.
Brent Ditch is generally assumed to be an Anglo-Saxon earthwork in Southern Cambridgeshire, England, built around the 6th and 7th centuries AD. However most of its structure has been lost over time. The site is scheduled as an ancient monument by Historic England.
Black Ditches is an earthwork close to the village of Cavenham of Suffolk, and part of it is a biological Site of Special Scientific Interest (SSSI). The earthwork is 4.5 miles long between the River Lark at Lackford and the Icknield Way. It is described by the Suffolk Historic Environment Record as having no direct dating evidence but "by analogy with other linear earthworks in the region it is usually assumed to be post Roman".
Burwell Castle was an unfinished medieval enclosure castle in Burwell, Cambridgeshire, England.
The Devil's Humps are four Bronze Age barrows situated on Bow Hill on the South Downs near Stoughton, West Sussex. They are situated on a downland ridgeway crossed by an ancient trackway, above Kingley Vale. The Devil's Humps are counted among the most impressive round barrows surviving on the South Downs. The Devil's Humps are within the Kingley Vale National Nature Reserve. The two bell barrows together with two pond barrows and a cross dyke are listed as Scheduled Ancient Monument 1008371, while the two bowl barrows are listed as Scheduled Ancient Monument 1008372.
The Roman Road in Cambridgeshire, also known as Worsted Street Roman Road, is a 12.4-hectare (31-acre) linear biological Site of Special Scientific Interest stretching from south-east of Cambridge to north of Linton. It is also a Scheduled Monument, and is maintained by Cambridgeshire County Council.
The Harcamlow Way is a waymarked walking route in England running in a figure-of-eight from Harlow to Cambridge and back again, hence its portmanteau name. On the way it runs through Essex, Hertfordshire and Cambridgeshire. The route is 141 miles long.
Earle, John (1865). Two of the Saxon Chronicles Parallel
Coordinates: 52°13′55″N0°21′32″E / 52.232°N 0.359°E