• Ali Isaac

reading the signs: understanding the megalithic artwork of the brú na bóinne complex

The three famous burial mounds of the Boyne Valley, Newgrange, Knowth, and Dowth, form the heart of a complex, sacred landscape dating back to the early Neolithic period, c. 4000BC. In 1993, the Boyne Valley was formally designated a UNESCO World Heritage Site (Smyth et al 2009 vi), and continues to excite the national imagination by revealing new, previously unknown archaeological monuments; ‘Dronehenge’, a pit circle dating to c. 2900BC, was discovered during the dry summer of 2018, as was a tomb with a highly decorated kerb stone at Dowth Hall (Maxwell 2018 www.archaeologyireland.ie).

This kerb stone is thought to be one of the most impressive examples of megalithic art unearthed in Ireland for decades. As such, it enhances the Boyne Valley’s pre–existing collection, which is recognised as comprising the most prolific concentration of megalithic art in Europe (Smyth et al 2009 vi).

Of Ireland’s total wealth of decorated stones, 70% can be found within the Boyne Valley (O’Sullivan 1997 19). This artwork has provided the basis for much debate since Newgrange was first discovered by antiquarians in 1699. Many theories have been proposed concerning the artwork’s meaning and purpose, although no definitive conclusions have been drawn.

During the nineteenth and early twentieth centuries, analysis of the Boyne Valley megalithic art focused on interpretation; popular theories ascribed astronomical associations with particular geometric motifs, whilst one antiquarian proposed that C4 at Newgrange was covered with Phoenician numerals (O’Sullivan 1986 69).

George Coffey claimed that Irish tomb art derived from Scandinavian rock art, although the latter was found to date to the Bronze Age, long after the Boyne Valley monuments were constructed (O’Sullivan 1986 69). Some years later, Joseph Dechelette suggested the abstract symbols represented facial images of a Neolithic funerary goddess (O’Sullivan 1986 69–70).

Anthropomorphic imagery dominated the scholarly imagination for much of the twentieth century; however, further excavations enabled detailed studies of a ‘wealth of newly unearthed tomb art’ in Ireland, leading to a more objective focus on the art forms and techniques, rather than potential meanings of individual motifs (O’Sullivan 1986 70–71). Whilst earlier analysis had led to speculative and unproven conclusions, this new clinical approach erred too much on the side of caution, prompting what O’Sullivan describes as an ‘observer–imposed selection of what may be accepted as tomb art [which] ignore[s] non–formal ornamentation such as extensive pick dressing’ (1986 71).

Kerbstones at Knowth

Excavations at Knowth by George Eogan in the 1960s revealed an interesting phenomenon with regard to its stone art. Some of the stones used in the tomb’s construction (eg. capstones 3, 5, 10 and orthostats 17, 18, 74 and 81, among others) appeared to have been positioned so that their decorated surfaces could not be seen; this was found to be true also of Newgrange, where various kerb stones (4, 13, and 18) were discovered to have artwork on the side facing into the mound (Eogan 1998 162–63).

Eogan realised that some of these stones had been repurposed; some capstones, for example, had an undecorated portion at one end, suggesting this was the socket end of a stone which had once served as an orthostat (1998 165).This indicates a sequence of monument building on the site, with a previous tomb being dismantled to provide materials for the construction of a new structure; Eogan suggests hiding the old, pre–existing decoration diminished the power of its symbolism (1998 165–168).

However, kerb stone 6 at Newgrange appears to be original to the construction of the tomb, yet its decorated surface is found in the socket, suggesting that in some cases, for reasons unknown, the art was deliberately hidden (Eogan 1998 171).

Just as the use of recycled stones indicates a history of monument building in the Boyne Valley, O’Sullivan believes that the decoration itself reveals a sequence of artistic evolution. In particular, the art at Knowth shows signs of continental influence not seen elsewhere in Ireland, with designs from Brittany being copied onto the stones of both western and eastern tombs, whilst the anthropomorphic image of orthostat L19 inside Newgrange is reminiscent of Iberian art (O’Sullivan 1997 20).

Many artworks show that new designs have been superimposed over older ones. These new designs are bold and distinctive in appearance, consisting of serpentiform motifs and large–scale parallel lines and arcs, and seem to be inspired by the shape and surface structure of the stone itself, often filling the whole face of the stone with little respect for pre–existing motifs; O’Sullivan labels these designs ‘plastic style’ (1986 74–76).

Plastic style decoration can be found in both tombs and on some kerb stones at Knowth (K11, and orthostats 41, 44, 48, and 49); they are found exclusively on surfaces which can still be seen, and do not extend below 30cms of the bottom of the stone, all of which suggests they were added after the stones were already in situ (O’Sullivan 1986 76).

Other designs, consisting of individual motifs such as spirals and circles, chevrons and lozenges, O’Sullivan distinguishes as ‘depictive style’; he claims these were traditional at the time of construction and appear on surfaces both visible and hidden (1986 75). With its bold form, and its positioning to the side and along the facing edges of its stone façade, plastic style art was clearly designed for maximum visual impact as one progressed along a tomb’s passageway.

Kerbstones at Newgrange

It is apparent, therefore, that the function of the art changed; whereas the traditional depictive motifs seemed to prioritise ritual over aesthetics, as O’Sullivan claims, the innovation of the new plastic style symbolised a shift ‘from art as expression to art as spectacle’ (1997 19).

In recent years, interest in interpretation has been revived. New spheres of archaeology have emerged, such as archaeoastronomy, which has established the now well–accepted theory of solar alignment.

The passage at Newgrange is aligned with sunrise on the morning of the winter solstice; the east and west passages at Knowth are aligned with sunrise and sunset on the Autumn equinox, respectively (Prendergast and Ray 2002 35), whilst Dowth North aligns with the winter solstice sunrise, Dowth South with sunset on the winter solstice.

These solar events were clearly of great importance to the community which built these monuments, perhaps providing a cycle of occasions to be marked and celebrated throughout the year. That the decoration itself might be thought to represent astronomical and solar events is no surprise.

According to Euan McKie, the artwork on kerb stone 15 at Knowth represents a Neolithic solar calendar, which he believes is authenticated by the British ‘menhir calendar’, a series of standing stone solar alignments, identified by A. Thom (2013 215). The design on K15 consists of a ‘a mass of pecked rings, spirals, and wavy lines… {and] an unusual fan-shaped pattern’, which McKie claims represents a sixteen ‘month’ solar calendar, copies of which can also be seen in cruder form at Newgrange and cairn X at Loughcrew (2013 215–218, 213).

Martha Doyle has a very different view; she believes megalithic stone art has a marine theme. She cites La Table des Marchands, a tomb in Brittany, as an example; it contains a carving of an axe on the ceiling, and marks on a triangular stone below the axe, which have been interpreted as ‘crooks’ (Doyle 2016 10). She believes this image represents stalks of marine kelp stacked in a heap to dry, that the axe was used in harvesting the seaweed, explaining that the coast of Brittany harbours the largest seaweed beds in the world which are still harvested today (Doyle 2016 10).

She claims Irish tomb art symbolises the harvesting of light; oriented on solar alignments, which often correspond with high or low tides, the art represents images of bioluminescent sea creatures, which had the ability to produce light (Doyle 2016 11). She compares the spirals on the Newgrange entrance stone with sea–slug eggs (Nudibranchia), and the triangle shapes with barnacles, the sea–slug’s main food source; this creature glows in the dark and spawns in January; the capturing of the winter solstice light could have been a celebration in anticipation of this extraordinary event (Doyle 2016 11).

She suggests that motifs found inside and outside of Dowth represent the bioluminescent Hydromedusa jellyfish, and that cairn T at Loughcrew contains a wide variety of such representations; by harnessing the light of solar alignments, the artists discovered a technology to make their art glow, just like the creatures themselves glowed (Doyle 2016 11).

Although the Boyne Valley monuments and Loughcrew are not located near the sea, she suggests the builders were a ‘coastal culture who progressed to inland farming but retained their coastal inspired beliefs’ (Doyle 2016 11). Whilst the similarities between the sea creatures and the motifs are certainly striking, as Robert G. Bednarik warns, ‘the semantics of prehistoric art is inaccessible to us’ (1990 79).

The abstract nature of Irish megalithic art has led to the view that it may have been inspired by shamanic altered states of consciousness. This theory, known as the neuropsychological model, attracted the attention of specialists from a wide variety of disciplines besides archaeology, including anthropologists and psychologists.

Megalithic motifs were categorised and compared with artwork of known shamanic cultures in Africa, and the Coso people of California; whilst this process described similarities between motifs, it did not, however, provide proof of the existence of Neolithic shamanic practices (Dronfield 375). Nor did it suggest why artists felt compelled to recreate their motifs on monument stone surfaces.

It did invite interpretations of a religious or spiritual nature, though; O’Sullivan suggested that the cup mark, a picked hollow which dates back to the Palaeolithic period, could be interpreted as the symbol for a tunnel leading into death, in much the same way as the passage leads into the tomb wherein lie the remains of the dead; this cup mark appears in profusion at the Boyne Valley complex, on one in every two stones at Newgrange, and on one in every nine stones at Knowth (O’Sullivan 1997 20).

The theory might also explain why some art was hidden, visible only to those of the spirit world, or experiencing shamanic journeying.

The neuropsychological theory suggests that both depictive and plastic styles of art perform an important visual role in the use of the tomb structures. In order to test this hypothesis, Rachel Opitz conducted an experiment in which the interior of Knowth was scanned into a virtual reality program which monitored participants’ eye gaze movements; the aim was to ascertain which elements dominated the visual experience of passing through the passage (Opitz 2017).

Results indicated, however, that the art was not the dominant feature in the passage for several reasons: concentration was directed towards safely navigating the passageway, therefore the overall pattern of stone arrangement, ie where it was safe to put one's feet and hands, was the primary focus; secondly, a motif such as a spiral, came into view and was passed in the space of two steps, which was not enough time for it to be noticed; additionally, lack of adequate lighting was also a factor (Opitz 2017 1216–18).

If the builders of the monuments processed through the passages in complete darkness, then clearly the decoration could have no significance at all until lit up by the sun’s rays on the relevant day of alignment. It may be that modern ‘preconceptions of what was important to someone in an imagined past’ have hindered rather than enhanced investigations (Opitz 2017 1222).

The desire to attach meaning to the symbolism of Irish megalithic art has sparked fierce debate. Much has been learned about the distant past by deciphering Egyptian hieroglyphics, and the cuneiform script of ancient Sumer. Not only do these prehistoric texts provide a contemporary historical narrative, but they reveal details of the religious beliefs, motivations, organisation, and daily life of the societies which made them; they provide a human connection to the past and our own origins. Decoding the enigmatic inscriptions left behind by the builders and artists of Ireland’s great ancient monuments is an elusive task which will continue to intrigue scholars for many years to come.


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Smyth, J. (ed.) 2009 Brú na Bóinne World Heritage Site Research Framework, The Heritage Council, Kilkenny.

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