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Thames Valley National Mapping Programme project

The archaeology of the Thames Valley is characterised by the cropmark remains of numerous prehistoric ritual sites and numerous settlements from the prehistoric to medieval periods with associated fields and trackways, forming landscapes which were traced over a number of kilometres. This intensive use is characteristic of lowland river valley locations throughout England with well-drained land ideal for cultivation and settlement, and the rivers offering water, communication and ritual foci.

Colour aerial photograph showing village in background with pasture and arable fields and then gravel pits in the foreground
Aerial view of Standlake village, Oxfordshire taken on 03-JUL-1990 showing the earthworks of the medieval settlement close to the village, and the cropmark remains of a probable Iron Age or Roman settlement in the nearer fields. In the foreground are recent gravel pits, some already filled with water. (NMR 4609/32). © Crown copyright. HE

The Thames Valley

The abundant river gravel deposits are steadily being quarried and flooded resulting in loss of many of these archaeological sites. The Thames Valley has been cultivated for centuries and much of the prehistoric remains were levelled and lie beneath the later medieval ridge and furrow, only visible as cropmarks from the air. Many sites recorded from earlier aerial photographs (some taken in the 1930s) had already been destroyed by more recent quarrying.

The village of Standlake in Oxfordshire illustrates the typical archaeological remains encountered throughout the Thames Valley with extensive multiphase Iron Age or Roman settlements consisting of hut circles, enclosures, ditches, pits, field system and trackways which have remained hidden beneath medieval settlement and ridge and furrow until the mid to late 20th century with a shift from predominantly pasture to arable farming.

The project

The survey utilised photographs dating from the 1930s to the 1990s. Because of the extensive aggregates extraction which has taken place along the length of the Thames Valley since at least the 1950s, the survey mapped numerous sites or parts of sites which had long since been destroyed, and many that have been subsequently removed since the end of the project. This is illustrated when the transcribed plots are overlain on the current map.

Colour image with archaeological features shown in red against a greyscale map background
This extract of NMP mapping depicts extensive prehistoric settlement remains visible as cropmarks and plotted from aerial photographs in the vicinity of the village of Standlake, Oxfordshire. The south-west area has now been destroyed by gravel extraction. Air photo mapping © Historic England; background © Crown Copyright and database right 2009. All rights reserved. Ordnance Survey Licence number 100019088. 2009.

The archaeology of the Thames Valley

Numerous prehistoric sites identified as ritual and funerary in nature have been recorded throughout the region. There were nearly a thousand Bronze Age barrows recorded, but of particular note were the Neolithic ritual sites clustered in close proximity (within 2km) to the river and its tributaries. These included four henges and 16 cursus monuments, six of which were new to the record. Also, a total of 12 Neolithic causewayed enclosures were recorded, three of which were new discoveries.

Colour aerial photograph showing arable fields containong cropmarks alongside a river with a lock and weir
The cropmark remains from many periods near Buckland photographed on 03-JUL-1990. They include the probable Neolithic causewayed enclosure and other features including two tracks meeting at a crossroads and numerous pits, ditches and enclosures. The underlying gravel and varying soil depths cause the dark patches which mask the archaeological remains (NMR 4609/22) © Crown copyright. HE

Highworth Circles

Of particular interest were a group of sites known as Highworth Circles. These are a cluster of circular enclosures typically 40 to 95 metres in diameter, with an external bank and internal ditch and no apparent entrance. In total 41 were recorded, with many still surviving as earthworks.

This is a little understood group of monuments and there are two schools of thought concerning their likely date and function. Based on morphology it was suggested that they represented a form of hengiform enclosure of prehistoric date. However, their sheer number and general confinement within the Hundred of Highworth supported by the results of excavation has led to the suggestion that they are medieval (13th-14th century) in origin and probably related to some form of stock management.

Colour aerial photograph showing a number of fields around a farm with a light dusting of snow
Enigmatic circular enclosures known as Highworth Circles at North Leaze Farm, Wiltshire photographed on 03-MAR-1995 (NMR 15218/5) © Crown copyright. HE

The key findings from the project can be found in the report:

The Thames Valley Project: A Report for the National Mapping Programme

The Thames Valley Project: A Report for the National Mapping Programme

Published 1 June 1994

NMP report from the Thames Valley Project

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