A henge is a man-made prehistoric structure dating from the Neolithic period and comprising a circular area delineated by a bank and usually a ditch, the bank being pierced by one or more entrances. Henges do not constitute an homogenous group of monuments. There are great variations within this broad category in the height of the bank and of the depth of the ditch, where present. The bank may be as high as 3 metres, for example at Durrington Walls in Wiltshire, and the ditch may be as deep as 6 metres, as illustrated by excavation at Avebury, Wiltshire, by Gray between 1908 and 1922 .
In the majority of henges the ditch is inside the bank but in the most famous henge, Stonehenge in Wiltshire, the 1.8 metre high bank was built inside the 2 metre deep ditch, although there is in addition a low counterscarp outside the ditch. They were categorised in Stuart Piggott’s survey of 1939 as dividing into two main groupings: those with one entrance falling into Class 1, while those with two or more were placed in Class II. In 1951 Atkinson subdivided the latter group, adding Class IIA to indicate henges with two concentric ditches enclosing a single bank and geographically restricted to Yorkshire. Subsequently, henge classification has been further subdivided to highlight those with a ditch external of the bank, such as Stonehenge itself and those with no ditch, for example Monknewtown, Co. Meath.
The sites vary greatly in size. High Knows in Northumbria, for example, has a diameter of 8.5 metres while Durrington Walls is 480 metres across. Further, although most henges are generally circular many show substantial irregularity, for example the diameter of Marden in Wiltshire varies from 315 metres to 518 metres, producing an oval shape although this may have been due to its siting adjacent to the River Avon.
Henges are a phenomenon of and are widely distributed throughout the British Isles with concentrations near Amesbury in Wiltshire, the Mendips, the upper Thames valley, around Ripon in Yorkshire, the Moray Firth and the Boyne Valley in Ireland. Apart from the Mendips group, they were not built on high ground but occupy lower-lying sites unsuitable for defence in warfare.
The construction of henge monuments exhibits similar techniques and tools to those employed in the Neolithic period for building causewayed enclosures and long barrows and digging mines such as Grimes Graves for flint extraction.
The circle may have been obtained by fixing one end of a rope at the desired centre, extending it to the radius required and using it as a guide for marking out the circle. With the shape marked on the turf in some way, perhaps by using river sand or powdered chalk produced by grinding suitable local deposits, the ditch could be dug with antler picks, shin bone “spades” and baskets. The material extracted would then be piled up outside the ditch to form a bank. At Avebury, there is evidence that additional material was brought from elsewhere and added to the bank. The henge originally had a deep ditch and there would already have been sufficient material on site to create the bank. There must therefore have been some additional significance for bringing other material to the henge.
An alternative construction method may be illustrated by the Giant’s Ring, Ballynahatty, Co. Down, where it appears surface material was scraped outwards from the entire inner enclosure of the henge and piled up to form the bank. This has left a slight inverted saucer cross-section of the enclosed area, accentuated by the possibility of a shallow internal ditch. Excavating the site in 1954, Collins suggested that the bank may have been constructed with steeper sides retained by boulder revetments. In addition, several henges exhibit variations in their bank which may indicate either multi-seasonal work or construction by several different groups at the same time, for example the Giant’s Ring and Avebury.
Although it is only possible to guess at the amount of labour available to Neolithic communities, archaeologists have estimated the resources required to construct several of the largest henges. Atkinson, for example, estimated that it would require 900,000 man-hours to produce Durrington Walls although Startin reduced this figure to 500,000 and suggested a workforce of between 250 and 500. For Avebury both archaeologists made equally varied estimates: Atkinson arriving at 1,500,000 and Stantin 500,000. The significant differences indicate archaeologists’ difficulty in assessing the effectiveness of the tools used and the extent of teamwork, planning and co-ordination of the Neolithic engineers. The work was probably undertaken during mid-summer when crops were ripening and involved whole communities, perhaps with any women and children not needed for tending animals or guarding crops helping to move ditch spoil.
Neolithic society is marked from the preceding Mesolithic period by the replacement of hunting and gathering by widescale farming through the domestication of animals and selective breeding of suitable cereal crops. This fundamental change meant that a local population would be largely sedentary, only moving as soils became exhausted. While there was probably little improvement in people’s health, such a society did generate the resources to support the substantial seasonal workforce needed for henge construction. Animal husbandry supplied high-protein food on demand and cereal cultivation and grain storage allowed the seasonal peaks and troughs of food availability to be largely levelled out and provide a regular diet.
The development of food stores and surpluses provided the conditions for specialisation of labour and the accumulation of wealth. Such social stratification may have led to the development of chiefdoms which were, perhaps, the form of community required to organise and control the large workforces needed to build henge monuments.
Contemporary with the development of henge construction was the introduction of Grooved Ware pottery, found at Neolithic sites throughout the British Isles. According to Parker Pearson flat-bottomed Grooved Ware pots developed in Orkney along with the earliest henge monuments, that at Stenness dating to 3300 BC. He suggests that it was the Orkneys’solar alignment that prompted the development of the henge structure and that Grooved Ware pottery spread outwards throughout eastern Britain, eventually to predominate in the large southern henges. The pottery displays a characteristic representation of woven basketry sometimes with the addition of regional variations reflecting, for example, designs in the Boyne Valley passage tombs and the pecked and incised mural art of Orkney. It is usually associated with pig bones, of which large quantities have been found at Durrington Walls suggesting extensive feasting.
According to Atkinson in 1951 henges may be dated by their cultural association, that is Class I henges were associated with Neolithic Grooved Ware, while Class II henges provide Beaker wares. Radiocarbon dating gave a mid-third millenium BC date for Arminghall in Norfolk and Llandegai in Caernarvonshire, while the great Wessex henges at Stonehenge, Avebury, Woodhenge, Durrington, Marden and Mount Pleasant were dated to the late third millenium BC. However, Parker Pearson states that Avebury has been redated to c.3200 BC and the first phase of Stonehenge to c.3000 BC, making both monuments about five hundred years older than previously thought. Recent dating evidence now suggests that henges gradually replaced some functions of causewayed enclosures towards the end of the fourth millenium BC and that they continued in use, some gaining timber and stone structures, until the mid-second millenium BC. This period covers the use of both Grooved and Beaker ware and would account for their presence at the wide range of sites identified as henges.
Archaeological excavation of henges has also revealed circles of spaced pits containing the remains of meat joints or of human cremations such as those subsequently inserted into the Aubrey Holes at Stonehenge and circular settings of post holes for vertical timbers, perhaps of buildings. The post hole evidence at, for example Woodhenge and Durrington Walls has led archaeologists to postulate large timber structures which may have been either enclosures or roofed buildings. These buildings may indicate settlement or ritual and although there is normally an absence of occupation evidence at henge sites at Mount Pleasant in Dorset and Marden and Durrington Walls there were middens and other domestic debris.
The most evocative and enduring structures within henges are, however, stone circles. They have their own distinct entrance, frequently associated with a pit, standing stone or post hole just outside. They also appear independently of henge monuments, for example over 100 henges have been identified in Britain and Ireland while Burl lists 368 stone circles in the same area and only a small minority of these appear inside henges. Nevertheless, their presence there has produced some of the most dramatic and intriguing monuments of the Neolithic and Bronze Age periods. In particular, the type monument at Avebury contains not only a large ring of stones within the ditch but also at least two further rings and is linked by the West Kennet Avenue of standing stones to the stone and timber Sanctuary, while the enigmatic Silbury Hill stands to the south.
Across Salisbury Plain to the south of Avebury stands Stonehenge itself, unique in that the stones of its most prominent sarsen circle and the trilithons and bluestones have been shaped and cut to accept lintel stones. After the initial construction of the ditch and bank in 2800 BC it was subsequently used for cremation burials and between 2000 and 1500 BC the Avenue was laid out and the bluestones brought to the site along, perhaps, with the sarsen stones. It appears that the final form of the structure had been established by 1500 BC.
Henges are alterations of the natural landscape by man. All such alterations have a purpose, even though it may not now be self-evident. These circular structures and the wood and stone circles often associated with them represented very large investments of resources. They were built to last and received alterations, renovations and additions. Their use continued for many centuries. They were abandoned, not demolished, although some, such as Avebury, had their stone circles later robbed of stone. Variations in size and style of henge probably represents a variety of functions.
Unlike Neolithic and Bronze Age fortifications, they do not seem to have been built for defence. In particular the ditch, where present, is usually placed on the inside of the bank making it unsuitable for defence and they are rarely placed on hill tops or other natural defensive sites. They display the substantial resources available to the communities that built them. Part of their function may have been to exhibit that wealth to surrounding communities. Megaw and Simpson suggest that many henges in the north of Britain were constructed to take over the causewayed enclosures’ role as trade sites for stone axes, that the large southern henges were built to act as new focal centres and the small ones were primarily funerary in character. Darvill states that the discovery of deposited mint condition Lake District axe heads ritually buried blade downwards at Llandegai henge in Gwynedd points to a connection between axe trade or gift exchange and henges. If they played such a role then they would be potent symbols of power and grandeur to visiting tribes.
Perhaps they were statements of territorial possession, as has been suggested for the earlier long barrows. Part of the function of the earlier causewayed enclosures may have been as sites for excarnation, the subsequent disjointed bones being placed in nearby long barrows, perhaps allowing the spirits of the ancestors to watch over the community and its lands. If large henges took over some of the functions of causewayed enclosures in, for example, the Wessex area, then they may have also assumed this assertive function of the long barrows.
Henges may represent formal entrances or transitions into or through territory or provide neutral meeting places. Multi-entrance henges appear to have attracted routes through them, for example at Avebury. In the Roman pantheon Janus, the two-faced god, was the guardian of entrances, facing both directions. The Romans were cautious to pass through propitious entrances wherever sacred enclosures occurred. It has been noted that some Roman roads run parallel to trackways through nearby henges and these alignments may represent their reverence for local beliefs, a reverence in which Roman imperialism expressed a rare benevolent attitude.
A popular conception is that henges, especially those containing stone circles, may have had astronomical significance. Whilst it is possible to recognise, for example, the alignment of Stonehenge with the midsummer solstice it is, perhaps, more conjectural to suggest that sightlines through stones may point to stars and constellations. The society that constructed henges was agricultural and Richards also points out that a more important alignment might have been looking into the henge on the 21st December when the midwinter sun set within the tallest trilithon, marking the shortest day and the turning point of winter. Empirical knowledge of the seasons and the resulting weather and day length would be well established through many generations of experience and passed on by aural tradition. Extensive country folk lore survives even to this day and indicates the wealth of practical knowledge inherited within agricultural societies. Neolithic agricultural society would not need a megalithic “sun dial” to predict the passing of the seasons but it may have required the reassurance that stellar and solar alignment could give to its understanding of time as a cyclical phenomenon as distinct from the modern concept of time as linear. This may have been part of the henges’ function, providing the special location for the formal acknowledgement of that annual cycle of events. Parker Pearson points out that it is not necessary to build monumental structures of standing stones and tree trunks to practice astronomy. Henges may have commemorated past events and preserved empirical knowledge.
If henges did take over some roles of the causewayed enclosures then they may have been mortuary enclosures, although this seems less likely as there is no apparent evidence of subsequent entombment of the disarticulated bones. On the contrary, the evidence at Stonehenge and Llandegai, for example, is of cremation burials. Henges often form the focal point for Bronze Age inhumations. The Stonehenge area is especially noted for round barrow “cemeteries” containing high-status burials although this may have been a secondary and later function. Nevertheless, these do not appear to explain where the burials occurred of the many low-status people whose labour built both henges and barrows and supported this aristocracy. It may be that funerary rites for those not of the highest status, the majority of the population of the period, if conducted at henges, had moved beyond the physical disposal of the body to a ceremony that symbolised the transition of the deceased’s soul to another plane. Parker Pearson suggests that most people were cremated in the late Neolithic and early Bronze Age and that their ashes were scattered or buried in shallow pits without any pots.
It is as carefully engineered ritual sites that henges seem the most compelling. Their very structure suggests special activities unconnected with the mundane labour of agriculture or the demands of defence and warfare. At Avebury, for example, material was brought to the bank from nearby hills and rivers perhaps to link those places with the ritual proceedings at the henge.
Primarily henges are circular, or nearly so. Such a shape occurs very infrequently in nature and rarely at this scale, especially in Britain and Ireland. At the Giant’s Ring considerable skill was displayed by the engineers in placing the circle as they were limited on one side by a steep slope yet were able to maintain the pre-existing passage tomb as the henge’s focal point. The geometric shape was retained despite the natural topography and the wish to incorporate the earlier tomb. By contrast, Neolithic causewayed enclosures tended to utilise the site’s natural contours.
Henges enclose an area in an unnatural way, giving that space a special purpose, defining a limited area. This suggests that whatever took place inside a henge was conducted by a specific number of special people, perhaps viewed by others standing on a flat-topped bank such as that at the Giant’s Ring. The circular shape also provides excellent acoustics. From the bank it is possible to clearly hear someone speaking in only a slightly-raised voice at the centre. Without reliable information of population density and settlement around henges it is impossible to estimate whether an entire local tribe could be accommodated around the henge walls or whether there was a further subdivision of society with some section excluded entirely from the ceremonies. The presence of Grooved Ware pots and animal bones at Durrington Walls, for example, indicate that feasting took place there.
The presence of one or more entrances suggest a procession, or perhaps certain sections of the participants entered by different entrances. Each entrance may represent a ritual gateway for specific parts of a tribe such as elders or warriors, men or women, or even perhaps different local tribes coming to participate together.
The importance of henges is emphasised in many instances by their containing wooden or stone rings or wooden structures. Apart from the work involved in constructing the henge itself, the addition of these other monuments further raises their importance. Timbers and stones will have had to have been brought from some distance. For example, Wainwright has calculated that phase 2 of the Southern Circle at Durrington Walls would have required 260 tons of timber, including entrance posts weighing over five tons each. Although much woodland still remained, despite forest clearance for Neolithic farming, such numbers of large trees would not be available in the immediate vicinity. To build Stonehenge more than 80 sarsen stones, weighing up to 50 tons each, were transported 25 miles from Marlborough Downs to the north, then dressed on site and raised into position. Further, even if the bluestones were locally available as glacial erratics rather than transported from Preseli Mountains of Pembrokeshire they still represent a substantial use of human resources.
Henges form part of a much larger ritual landscape, for example the grouping of monuments at Milfield in Northumberland. They are associated with cursus, avenues of stones and Bronze Age high-status burials. In a remarkable book Dames suggests that there was a direct relationship between Avebury henge, avenue, Sanctuary and Silbury Hill in which the season’s passing was celebrated in a Neolithic “harvest festival” ceremony. He suggests that Silbury Hill represented the Mother Goddess and that each late summer the ripe crop growing on its flattened summit was sacrificially harvested to coincide with the return of the Winter Bourne spring near the Sanctuary, the surrounding hills forming a natural amphitheatre. In addition he claims that the outline of Silbury Hill and its ditch, when filled, closely follows the shape of the Mother Goddess figure found in the Hal Saflieni hypogeum in Malta, dated to about the fourth millenium BC, and represents a widespread worship of the Earth and its annual cycle of seasons. Whereas Dames’ novel ideas may not survive close scrutiny, the point is that Neolithic agriculturalists undoubtedly had some religious beliefs. The significance of Dames’ interpretation is that he is attempting to link henges, their associated structures and the natural topography within a larger ritual landscape and suggest their relevance to an early society based on farming. In his interpretation of Avebury, Burl like Dames’ suggestions for Silbury Hill, stresses its association with ritual fertility cults marking the annual cycle of death and rebirth and draws parallels with more recent stone-technology agricultural societies.
Neolithic and Bronze Age people were no less intelligent or aware of their environment than contemporary society. They needed reliable knowledge of the seasons and the length of winter and summer. No doubt they sought to influence climatic affects by ritual intervention. Perhaps the main reasons why so much effort and resources were put into constructing henge monuments was their need to retain essential knowledge, to formally mark the seasons of the agricultural year, to cope with mortality and to stamp their ownership on land. Although such a diverse mix of intentions may seem strange to modern society, in such agricultural communities the combination of “natural philosophy”, ritual and territorial possession embodied in henges may have presented them with a satisfying, pertinent, subtle and holistic view of the world in which they lived.
Works referred to:
Burgess, C., 1980, The Age of Stonehenge, London, J M Dent.
Burl A., 1979, Prehistoric Avebury, London, Yale University Press.
Burl, A., 1995, A Guide to the Stone Circles of Britain, Ireland and Brittany, London, Yale University Press.
Dames, M., 1976, The Silbury Treasure, the Great Goddess rediscovered, London, Thames and Hudson.
Darvill, T., 1987, Prehistoric Britain, London, Routledge
Harbison, P., 1988, Pre-Christian Ireland, From the First Settlers to the Early Celts, London, Thames and Hudson.
Megaw, J. V. S. and Simpson, D. D. A., 1979, Introduction to British Prehistory, Leicester, Leicester University Press.
Morana, M., undated (c. 1980), The Hypogeum, a Jewel of Ancient Malta, Valetta, Government of Malta
Parker Pearson, M, 1993, Bronze Age Britain, London, Batsford/English Heritage
Richards, J., 1991, Stonehenge, London, Batsford/English Heritage.
Wainwright, G., 1989, The Henge Monuments, Ceremony and Society in Prehistoric Britain, London, Thames and Hudson.