The Raw Dykes Roman aqueduct

Reasons for Designation

The Raw Dykes represents a rare survival of a Roman water control feature in an urban context. It is particularly unusual in that it could not have operated on the more usual gravity flow principle utilized elsewhere in Britain, and thus represents a segment of a comparatively complex system which would have required both intensive labour and considerable engineering skills to construct. The remains of the Raw Dykes survive well in the form of a series of substantial earthworks. Since only a small section of the earthworks have been subjected to archaeological excavation the remainder of the site is comparatively undisturbed and will therefore retain significant potential for the survival of buried deposits. As a result of the survival of both historical and archaeological documentation relating to the site the remains are quite well understood. The location and accessibility of the Raw Dykes considerably enhances its function as a public amenity.

Details

The monument includes the remains of a Roman aqueduct known as the Raw Dykes situated immediately west of the junction of Aylestone Road and Saffron Lane, Leicester.

The monument includes linear earthworks up to 110m in length and orientated on an approximately north east-south west axis following the 60m contour. The remains consist of parallel banks defining a flat-bottomed linear depression approximately 110m in length, a maximum of 20m in width and 2.5m in depth. The north western bank reaches a maximum height of approximately 4m above ground level on its western side and is up to 17m in width at its base. The south eastern bank rises to a height of about 2.5m above the central depression on its western side but is only approximately 0.6m high on its eastern side due to a rise in ground level. The Raw Dykes are considered to represent the remains of a Roman aqueduct or water channel constructed to supply the settlement of Ratae Corieltauvorum.

The earliest known documentary reference to the earthworks is contained within the Lord Mayor's accounts for the Borough of Leicester of 1322 which refer to the `Rowedick'. The etymology is considered to suggest that the name was originally derived from the linearity of the earthworks, the present form `Raw Dykes' representing a corruption of this. Numerous references within land deeds over the following centuries suggest that the earthworks were formerly far more extensive, an early-17th century account recording that they then terminated `not five hundred paces from the south gate'. A contemporary diary kept by a Royalist officer during the Civil War suggests that a section, if not the complete length of the earthworks, was utilized by the Royalist forces besieging Leicester in 1645. The earthworks are clearly depicted in an early 18th century engraving, and a subsequent survey and description at the beginning of the 19th century recorded that sections had been levelled for a turnpike road and a racecourse. A map of 1885 depicts the Raw Dykes as continuing for a further 400m northwards of the 110m length visible today, subsequent development having reduced them to their present length by the early 20th century. Excavations in 1938 recovered pottery suggesting that the earthworks were constructed during or immediately after the first century AD and consisted of banks defining a broad ditch within which was a much narrower central channel. The layout and nature of the earthworks are considered to suggest that the narrow cut within the centre of the ditch represented the main water channel and was designed to increase the flow of water by concentrating it within a constricted space. In addition the orientation of the earthworks suggests that the Saffron or Knighton Brook, located approximately 1km south of the site would have been the most plausible source of water to feed the aqueduct.

All fences and modern surfacing are excluded from the scheduling although the ground beneath them is included.

MAP EXTRACT The site of the monument is shown on the attached map extract.

Legacy

The contents of this record have been generated from a legacy data system.

Legacy System number:

30218

Legacy System:

RSM

Sources

Books and journals
The Victoria History of the County of Leicester, (1907)
Mellor, J E, Memo to R. Rutland, P. Liddle - Rawdykes, (1988)
Stukeley, W, Itinerarium Curiosum, Volume 1, plate 26, (1766)
Wacher, J, The Towns of Roman Britain, (1974)
Bateson, M (ed), Records of the Borough of Leicester 1103-1327, (1899)
Bourne, J, Place-names of Leicestershire and Rutland, (1981)
Nichols, J, The History and Antiquities of the County of Leicester, (1810)
Keay, W, The Raw Dykes, Leicester. A Roman Aqueduct, (1933)
Kenyon, K, Exacavations at the Jewry Wall Site, Leicester, (1948)
Leicestershire Museums Service, , Raw Dykes: A Roman Earthwork, (1995)
Long, C E (ed), Camden Society Old Series in Diary of Marches of Royal Army During Civil War by R. Symonds, Vol. 74, (1859)
Stephens, G R, Britannia in Civic Aqueducts in Britain, (1985)

Other
Title: Ordnance Survey 25" Series Source Date: 1885 Author: Publisher: Surveyor:
Ancient Monuments Record Form, (1920)

End of official list entry

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