rims or sherds with a distinctive profile. Only two fragments of polished stone axes have been found so far, though there are a number of flints, including scrapers, blades, points, saws and leaf arrowheads. Unfortunately, however, the soil is so acid that bone does not survive and the condition of the Neolithic pottery suggests that some may have disintegrated altogether in the acid soil. Whether or not the sample hitherto excavated proves typical remains to be seen, but certainly the finds hitherto from Briar Hill are poor when compared to the riches from Windmill Hill.

Great Wilbraham

The sixth causewayed camp to be excavated in recent years, that at Great Wilbraham in Cambridgeshire, was only briefly mentioned at the Symposium, due to the untimely death of David Clarke who, with John Alexander, was the moving spirit behind it.

In two short seasons, 1975 and 1976 (when Ian Kinnes shared the direction) the two, possibly three, concentric ditches were sampled in three places and two areas of the mere, which surrounds on three sides the low gravel knoll on which the camp lies, were excavated. The interior proved to have been disturbed to the surface of the gravels, but the plough soil was rich in neolithic pottery and stone objects. The ditches also contained much pottery and animal and plant remains. Excavations in the mere also recovered much organic material, pottery and flint, some of it contemporary with the camp.

Air photography

But excavation has not been the only advance in our knowledge of causewayed camps in recent years. The contribution from air photography has been in many ways even more remarkable and has led to a revolution in our knowledge of their numbers and distribution.

In an article on causewayed camps in Economy and Settlement (edited D. D. A. Simpson, Leicester University Press) in 1971, Isobel Smith listed 17 known causewayed camps. In Antiquity for 1975, however, David R. Wilson of the Department of Aerial Photography, Cambridge, added 16 further examples, virtually doubling the number and extending the distribution over eastern England and the Midlands up to the Trent. Thus in the current Proceedings of the Prehistoric Society for 1976, Roger Palmer was able to list 30 definite sites and a further 13 possible sites, making 43 in all.

These new additions have not merely increased the numbers but have also radically altered the distribution and typology. Whereas the original causewayed camps were located on the chalk downs of Wessex and Sussex, the new additions are mostly found in lowland situations on the river gravels of the Thames and East Anglia and the tributaries of the River Trent. Types too appear to be different, for whereas Windmill Hill has accustomed us to the idea of causewayed camps with widely separated circuits of ditches, the majority of the new examples have two or three rings of ditches close together: Orsett, Briar Hill, Offham Hill, and indeed Crickley Hill all conform to this new pattern.

Thus in his current analysis in P.P.S. Roger Palmer has suggested that we should see four possible groupings, the Wessex group, which tend to be associated with long barrows, the Sussex group, which tend to be sited well away from long barrows, the Thames group, including the well known sites at Abingdon and Staines, and a Midlands group including major sites at Fornham All Saints, Suffolk; Freston, Suffolk; Alrewas, Staffs., Cardington, Beds., and Sawbridge¬ worth, Herts. In particular the site at Freston now looks extremely interesting, as recent air photographs have not only completed the circuit of the ditches, but also revealed in the interior what appears to be a building 120 feet long and 30 feet wide with probably 21 posts to a side and continuous trenches at the ends.

Ritual?

If, as Isobel Smith suggested, the sheer variety of the recent excavations show that too much had been extrapolated from Windmill Hill, yet one important result does seem to survive from her original Windmill Hill report. Virtually every speaker allowed that the causewayed camps were non-functional, indeed the word 'ritual', so long taboo in British archaeology, was used by most of them. Clearly many of the details of Windmill Hill are not repeated elsewhere, such as the richness and the variety of the imported goods. But nevertheless, with the possible exception of Crickley, none of them appear to be habitation sites. The concept of a meeting place does, perhaps still survive, either as a neutral zone on tribal boundaries, or as the focus at the centre of tribal territory. In putting such ideas into our minds Isobel Smith did perhaps, after all, set us on the right track.

or Defensive?

Perhaps the most remarkable aspect of the new excavations is the hint of defences found at both Hambledon Hill and Crickley, at Crickley clearly succeeding the causewayed camps, though at Hambledon the chronological relationship is uncertain. Until quite recently defensive structures were quite unknown in the Neolithic, but in his excavations at Broome Heath in Norfolk (P.P.S. 1972) Geoffrey Wainwright located what appeared to be a defensive bank and ditch with a radiocarbon date of around 2217 b.c., though as this formed a C shaped enclosure with a marked open side, it is difficult to know how seriously this was intended for defence. Nevertheless, if Hambledon and Crickley are truly to be interpreted as defensive structures, then perhaps we must consider anew the character of the middle Neolithic.

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