Monument record 4809/1 - Briar Hill Neolithic Causewayed Enclosure

The site of a Neolithic causewayed enclosure at Briar Hill. The site lies on the gentle north facing slope of the Nene Valley, the river itself lying 700 metres to the north. It was discovered during aerial survey in 1972 and excavated in 1974 to 1978 in advance of housing development. The cropmarks were interpreted and transcribed by RCHME in 1995 as part of the Industry and Enclosure in the Neolithic Project. The enclosure itself comprises two main concentric ditch circuits of interrupted ditch lying between 15 and 28 metres apart. The outer enclosure measures circa 200 metres by 190 metres, covering an area of about 3 hectares. Within the enclosure, to the east and sharing part of the inner ditch circuit is a smaller, sub-circular interrupted ditched enclosure roughly 90 metres in diameter and enclosing circa 0.6 hectares. Excavation showed this inner enclosure to be integral with the main inner circuit, the two forming a continuous spiral. Excavation also confirmed the cropmark indications that the interior contained few contemporary structures other than some scattered pits. Excavations showed that the ditches had experienced several episodes of recutting. Finds were concentrated particularly in the segments of the innermost enclosure ditch, and included potsherds, flints, fragments of stone axes, querns and polishing stones. Several pits contained later Neolithic material including sherds of Grooved Ware, Peterborough Ware and Beakers. A small group of Bronze Age cremations was found on the south west side of the outer enclosure, just inside the edge of the ditch. Four were in bucket-shaped urns and one was accompanied by a barbed and tanged arrowhead. Recent research into the dating of the causewayed enclosure suggests that construction probably took place in 3760-3415 cal BC. The estimate for the early Neolithic disuse of the ditches is probably 3340-2955 cal BC. According to this interpretation the enclosure was in use probably for 150-505 years. Part of the Hunsbury Hill Complex.

{1} Excavation of Neolithic causewayed enclosure on Briar Hill; enclosure of c.3ha; consisted of 2 concentric interrupted ditch circuits 15-20m apart; in use from mid C4th-mid C3rd BC; Internal features included pits & foundation slot for subrectangular wooden structure; Finds of Neolithic pot sherds including earlier Neolithic Grimston style wares and later Neolithic Grooved ware & Mortlake & Fengate type ware & Beaker sherds; also worked flints & fragments of stone axes of Groups I & VI & VII & XX; also rubbing stones & polishing stones;

A series of radio-carbon determinations for samples from the ditch fills suggests that the original construction of the site took place in the mid 4th millenium BC and that the final recutting of the inner ditch circuit, at least, was not later than the mid 3rd millenium BC. Several features of Neolithic date were found in the inner enclosure, and most if not all post-date the final reconstruction of the earthworks. Charcoal from one of a number of small pits has been dated 2420 BC +/-80 and from two pits 26m apart which may have been footing for massive posts there are dates of 2340BC +/-80 and 2300BC +/-70. One of the most interesting features of all was the foundation slot of a small but substantial sub-rectangular wooden structure, and this contained sherds of grooved ware and charcoal dated 2060 BC +/-90.

{3} Air photos show a roughly circular enclosure about 4ha in extent, bounded by two concentric, discontinuous ditches. Within it, on the east side, is a smaller circular enclosure formed by a third ditch which appears to branch from the main inner circuit. Crossing this innermost ditch is a sub-rectangular enclosure measuring approx 25m x 30m and there is a similar sub-rectangular enclosure to the north west. A fluxgate-gradiometer survey carried out by the Ancient Monuments Laboratory of the Department of the Environment produced a much more detailed plan of all these features and suggested the presence of others.

{5} Several features of neolithic date were found in the inner enclosure, and most if not all of these post-date the final reconstruction of the earthworks. Charcoal from one of a number of small pits has been dated 2420 bc + 80 (HAR - 4074), and from two pits 26 m. part which may have been footings for massive posts there are dates of 2340 bc + 80 (HAR - 2625) and 2300 bc + 70 (HAR - 4057). One of the most interesting features of all was the foundation slot of a small but substantial sub-rectangular wooden structure, and this contained sherds of grooved ware and charcoal dated 2060 bc + 90 (HAR 2607).
Other evidence of the use of the site during the later neolithic period including sherds of Mortlake and Fengate style impressed ware and Beaker pottery found in the final silt of the ditches, and several pits, producing radio-carbon determinations ranging from 1840 bc + 100 (HAR - 4073) to 1590 bc + 80 (HAR - 2389), which had been dug into these final infill layers.
A small group of Bronze Age cremation burials was discovered on the S.W. side of the outer enclosure, 9 m. inside the inner edge of the inner ditch. This comprised a cluster of shallow pits, at least 10 of which contained surviving cremation deposits. Four of these were in badly decayed, bucket-shaped urns, one being radio-carbon dated 1230 bc + 70 (HAR - 4065). Of the remainder, one, which gave a date of 1750 bc + 150 (HAR - 4058), was accompanied by a flint barbed-and-tanged arrowhead.

{20} Excavations on the enclosure were carried out by the NDC Archaeological Unit between 1974 and 1978, when approximately half the total area was investigated. The Neolithic enclosure in its entirety measures 206 m x 192 m, is roughly symmetrical on a north west - south east axis, and consists of two main complete and concentric ditch circuits, 14m-16m apart. On the east side the inner of these two ditches curves in a continuous right hand spiral to define the elliptical inner enclosure which measures 92m x 84m. The inner ditch was located in a trench for a gas pipeline, and the continuation of the outer ditch shows faintly in some of the air photographs. On the west side of the outer enclosure a gap in the outer ditch circuit and two opposing gaps in the inner ditch were associated with pits which may represent the remains of entrance structures. If so, these were not necessarily all contemporary. Another gap in the inner ditch on the south west side of the enclosure may also have been an entrance, but the evidence to support this idea is slight. No direct evidence survived of any banks associated with the ditches. In the fill of many of the excavated outer ditch segments, however, the collapse or slumping of a bank is suggested by large tips, often of loose ironstone rubble, deriving from the inner edge. Similar evidence indicates that there may have been mounds or banks at the north and south ends of the inner ditch spiral, between the overlapping ditch segments. No evidence was found of timber palisades or revetting associated with the ditches, apart from a series of four shallow post pits along the inner lip of the inner ditch on the south east side of the inner enclosure.
The main inner and outer ditch circuits consisted of steep sided, flat bottomed pits or segments separated by ‘causeways’. The size of individual segments varied considerably within each circuit; most were between 1.5m - 2m in depth below the present subsoil. In general the outer ditch segments excavated were slightly narrower and more shallow than those of the main inner ditch. The segments of the spiral arm of the inner ditch all tended to be relatively small and shallow, none being deeper than 1.5 m. Perhaps the most important single result the excavation of the ditches has been accumulation of stratigraphic and other consistent evidence for the repeated recutting of ditch segments which points to a prolonged, if perhaps intermittent, use of the site during the Neolithic period. The stratification of the infill of each individual cut is almost invariably consistent with a large natural, and presumably slow, process of silting, assisted by the collapse in some places of bank material, yet in nearly every instance recuts are from a level high in the secondary silt of the preceding phase. From this it seems probable that the earthwork was reinstated on a grand scale several times at long intervals, although the reconstruction may not necessarily have been complete on each occasion. Hardly any indication of recutting was found in segments of the outer ditch excavated on the north side the enclosure, and it would seem that here, for much of the time, the outer circuit may not have been complete.

The first dates obtained from samples from the ditches support the stratigraphic evidence of a long chronology. Charcoal from just above the primary silt in one of the segments of the outer ditch on the north side of the enclosure gave a date of 3490 ± 110 BC. A second date of 1590 ± 80 BC obtained for a Late Neolithic/ Early Bronze Age pit dug into the fill of the final major recut of an inner ditch segment provides a terminus ante quem for the final silting of the ditch at that point. The stratification of Neolithic pottery in the ditches is consistent with these dates.

{23} A reappraisal of the controversial early radiocarbon dates which suggested that the causewayed enclosure had been constructed in the fifth millennium cal BC, which would have made it the earliest such monument in Europe and Britain's earliest agricultural site. Only the final phase can be confidently dated to the later fourth millennium cal BC. The original interpretation is based on two samples which are suspected to be residual. This conclusion can be tested by dating the surviving remains of some samples.

{27} SP73625923. This site was plotted by the Air Photography Unit of RCHME in June 1995. This was a 1:2500 scale, level 3 photogrammetric survey which was carried out as part of the Industry and Enclosure in the Neolithic Project

{5, 29, 30} The 1974-78 excavations have been published in full. Note however that there has subsequently been much debate concerning the interpretation of the radiocarbon dates, the identification of the Neolithic pottery, and the suggested sequence for the 3 ditch circuits identified.

{30} The Neolithic causewayed enclosure at Briar Hill became the subject of controversy when radiocarbon dating appeared to show that it had been constructed in the fifth millennium cal BC, and maintained for about a thousand years (Bamford 1985). If true, this interpretation made Briar Hill the earliest known causewayed enclosure in Europe, and Britain's earliest agricultural site (Kinnes and Thorpe 1986). Doubts were raised about the contextual reliability of the radiocarbon samples, given the artefactual evidence, which only indicated occupation from the later fourth millennium cal BC onwards (ibid). This report assesses each radiocarbon result, and the interpretations of these results. The results and interpretations are then reassessed, using new techniques of radiocarbon date calibration and chronology modelling. The report finds that only the final phase of maintenance of the enclosure can be confidently dated, to the later fourth millennium cal BC, and that the original interpretation depends entirely on the contextual reliability of two samples. It cannot be proved that these samples were residual, but are reasons to suspect that they were, in addition to the artefactual evidence.

{31} Briar Hill was included in recent research into the dating of Early Neolithic enclosures. The results suggested an estimated construction date probably of 3760-3415 cal BC. The estimate for the early Neolithic disuse of the ditches is probably 3340-2955 cal BC. According to this interpretation the enclosure was in use probably for 150-505 years.
The results place the construction of the enclosure within the fourth millennium cal BC, rather than in the later part of the fifth millennium as suggested by Bamford. It is most likely to have been built in the middle centuries of the millennium. The chronological sequence between the three ditches remains unresolved. Mercer's suggested later Neolithic date for the spiral ditch is now thought unlikely due to the concentration in it of early Neolithic artefacts. The models also agree in placing the final infilling of the enclosure ditches in the second half of the fourth millennium or the first half of the third millennium cal BC, probably in the last third of the fourth millennium. It is possible that there was continuity of use of the site into the third millennium cal BC, with the timber structures of phase VIII. The Briar Hill enclosure was apparently in use for several centuries.
Reliable evidence for the dating of the Briar Hill enclosure is limited, and reflected in imprecise chronological estimates provided by the models. The outer ditch and the spiral ditch are dated only by radiocarbon measurements which provide termini post quos for their contexts.

<1> Royal Commission on The Historical Monuments of England, 1985, An Inventory of The Historical Monuments in The County of Northampton, p.274-5 (checked) (Series). SNN77383.

<2> Brown A.E. (Editor), 1974, Archaeology In Northamptonshire 1973, 9/84 (unchecked) (Article). SNN9109.

<3> BAMFORD H.M., 1976, Briar Hill - First Interim Report: November 1974 - March 1976, p.7 (unchecked) (Article). SNN71074.

<4> Wilson D.R., 1975, 'Causewayed Camps' and 'Interrupted Ditch Systems', p.178-85 (unchecked) (Article). SNN55845.

<5> Bamford H., 1985, Briar Hill Excavation 1974-1978, (unchecked) (Full Report). SNN55846.

<6> Brown A.E. (Editor), 1977, Archaeology in Northamptonshire 1976, p.209 (unchecked) (Report). SNN723.

<7> Brown A.E. (Editor), 1978, Archaeology in Northamptonshire 1977, p.179-80 (unchecked) (Journal). SNN2192.

<8> Rowley R.T.; Fowler W.J. (Editors), 1974, South Midlands Archaeology: CBA Group 9 Newsletter (4), 22 (Newsletter). SNN17341.

<9> Council for British Archaeology, 1976, South Midlands Archaeology: CBA Group 9 Newsletter (34), 33-5 (Newsletter). SNN104928.

<9> Selkirk, A. & W. (Eds), 1980, Current Archaeology, 71/358-63 (unchecked) (Journal). SNN108774.

<10> Hall, D N, 1977, South Midlands Archaeology: CBA Group 9 Newsletter (7), p.8-9 (unchecked) (Newsletter). SNN27911.

<11> HALL D.N., 1978, South Midlands Archaeology: CBA Group 9 Newsletter (8), p.40 (unchecked) (Newsletter). SNN60830.

<12> Current Archaeology, 52-3 (Article). SNN55803.

<13> BAMFORD H., Current Archaeology, p.358-63 (unchecked) (Article). SNN55804.

<14> Current Archaeology, 339-40 (Article). SNN55805.

<15> RAHTZ P., RESCUE ARCHAEOLOGY, PL26 (Series). SNN55046.

<16> Brown A.E. (Editor), 1973, Archaeology in Northamptonshire 1972, 26 (Journal). SNN8956.

<17> Northamptonshire SMR Collection of Aerial Photographs, Used with NMR & CUCAP collections (Aerial Photograph(s)). SNN104822.

<18> BAMFORD H.M., 1974, Briar Hill Excavation 1974-1978: Microfiche Volumes 1-4, (unchecked) (Report). SNN75425.

<20> Bamford H., 1979, Briar Hill Causewayed Enclosure: Second Interim Report, April 1976-October 1978, pp.3-10 (unchecked) (Article). SNN22419.

<21> Selkirk, A. & W. (Eds), 1975, Current Archaeology, 49/52 (unchecked) (Journal). SNN108772.

<22> Selkirk, A. & W. (Eds), 1977, Current Archaeology, 58/339-40 (unchecked) (Journal). SNN108773.

<23> Meadows, J., 2003, Dating Briar Hill: interpreting controversial results from the Neolithic causewayed enclosure at Briar Hill, Northamptonshire (Report). SNN111422.

<24> Jordan, D, Haddon-Reece, D, and Bayliss, A, 1994, Radiocarbon Dates from samples funded by English Heritage and dated before 1981, p. 120-122 (Monograph). SNN112521.

<25> Bartlett, A, 1974, Geophysics: Briar Hill, Northampton (Report). SNN113640.

<26> Shaw M.; Williams J., 1971-1981, Northampton Development Corporation SMR Record Cards, P113; P76A (Index). SNN133.

<27> Dyer, C, 1995, RCHME: Briar Hill Causewayed Enclosure Project (Archive). SNN114643.

<28> Dyer, C, 1995, Industry and Enclosure in the Neolithic Period (Archive). SNN114644.

<29> Kinnes, I and Thorpe, I J, 1986, Radiocarbon Dating: use and abuse, p. 221-3 (Article). SNN114646.

<30> Evans, C, 1988, Acts of Enclosure- a consideration of concentrically-organised causewayed enclosures, p. 85-90 (Chapter). SNN114645.

<31> Whittle, A, Bayliss, A and Healy, F, 1988, Chapter 6.3.1, Briar Hill, p. 293-300 (Chapter). SNN114647.

<32> Jordan, D, Hedges, R, Otlet, R, Switsur, R and Walker, J, 1994, Radiocarbon Dates from samples funded by English Heritage between 1981 and 1988, p. 214-5 (Monograph). SNN112643.

Record last edited

Feb 10 2025 7:27PM