W2B-027 Atlantic fortifications-0.txt
Atlantic fortifications Ð THE DUNS OF THE ARAN ISLANDS

Stone forts are a common element of the archaeological record in the west of Ireland and are particularly numerous in areas such as the Dingle peninsula in Co. Kerry, the Burren in Co. Clare and parts of west Donegal. The majority are regarded as cashels Ð the stone equivalent of the earthen ringforts which occur throughout the country, and which are generally considered to be homesteads dating to the Early Christian period.

The Western Stone Fort project was set up to look at a specific group of large stone forts, which are distinguished from the majority of cashels and promontory forts by their commanding locations, highly developed defensive features and distinctive architecture. About thirty or so of these forts are known to exist, with Grian&/an Aileach, Co. Donegal, Staigue, Co. Kerry and D&/un Aonghasa on the Aran Islands, Co. Galway, being the best known examples.

In the second half of the nineteenth century D&/un Aonghasa in particular received much attention from scholars, antiquarians and romanticists some of whom at least shared the view of William Wilde that the fort was a'stronghold prepared as the last standing place of the Firbolg aborigines of Ireland'." As a result perhaps of their perceived heroic status, almost half of these large stone forts were restored during the Celtic Revival movement towards the end of the last century. Since then, with the exception of the pioneering work carried out by T.J. Westropp in Co. Clare, most of these monuments have not been closely studied. One of the primary aims of the Western Stone Fort Project is to compile an inventory of these large stone forts, examine their distribution and siting, and compare their architectural features.

Substantial archaeological excavation has been carried out this century at four sites: Cathair Chom&/ain, Co. Clare, and Leacnbuaile, Dunbeg and Loher, Co. Kerry. The majority of the published examples have been assigned by their excavators to the Early Christian period, but there is evidence for earlier activity at Dunbeg, where charcoal from a ditch or trench predating the stone rampart yielded a radiocarbon data of 802-534 cal. BC. The eighth-century AD date which the excavator assigned to Cathair Chom&/ain in 1938 is now challenged by archaeologists who suggest that some of the artefacts found there could well have a pre-Christian date.

There are other indications of a pre-Christian origin for some of these forts. The presence of a chevaux de frise (upright pillars of stone set at close intervals as a defensive obstacle) at D&/un Aonghasa and D&/ucathair on Inis M&/or, Aran Islands and at Cathair Bhaile Cinn Mhargaidh (Ballykinvarga) in the Burren, suggests links with forts in Spain, Wales and Scotland where this feature also occurs. Architecturally many of the Irish sites are comparable to Iron Age stone forts along the Atlantic seaboard of western Europe. Whether these links represent the spread of ideas, or the movement of people along the Atlantic seaways is a matter of opinion at present, but some scholars would look to this route as the possible artery along which Celtic influences first reached Ireland. Looking at the Irish forts then against the background of contemporary settlement and culture in the area often referred to as 'the Atlantic Province' also forms part of the Western Stone Fort Project.

The forts on the Aran Islands

Most of the fieldwork associated with the project to date has been concentrated on the Aran Islands. The Aran Islands are strategically located across the mouth of Galway Bay and are outliers of the main Burren limestone plateau. The islands are noted for their wealth of archaeological remains, outstanding among which are seven large stone forts. Four of these (D&/un Aonghasa, D&/ucathair, D&/un Eoghanachta and D&/un Eochla) are located on Inis M&/or, the largest of the three islands; D&/un Chonch&/uir and D&/un Fearbha&/i are located on Inis Me&/ain and D&/un Formna lies on Inis O&/irr, the smallest and most southerly of the three islands.

The forts vary considerably in size and in the complexity of their defences. D&/un Aonghasa, with an enclosed area of 5.7 hectares (14 acres), is by far the largest, and the labour required for its construction implies a considerable community effort. Whether that effort was voluntary or in response to a coercive power we can only surmise, but such an elaborate undertaking would appear to have been prompted by political or military factors. In contrast, the simple univallate fort of D&/un Eoghanachta encloses less than a third of an acre and may have been built to reflect the status or power of a wealthy individual. D&/un Fearbha&/i and D&/un Formna are also univallate sites, though larger and of more irregular plan. A medieval towerhouse now stands in the interior of D&/un Formna. Three of the forts (D&/un Aonghasa, D&/un Eochla and D&/un Chonch&/uir) are multivallate. D&/un Chonch&/uir was additionally protected on the eastern side by a substantial bastion. The remaining site, D&/ucathair, is a promontory fort defended by a massive stone wall, with the chevaux de frise providing an additional line of defence on the landward side. Its exposed location has resulted in severe erosion of the upstanding remains since it was first recorded by the Ordnance Survey in the nineteenth century.

The remains of huts are visible in the interiors at D&/un Chonch&/uir, D&/ucathair and D&/un Eoghanachta. A variety of ground plans are represented Ð circular, heel-shaped, rectangular with rounded corners, and irregular. Without excavation it is not possible to assign a date to these huts. The examples at D&/un Eoghanachta certainly postdate the constuction of the fort and may belong to a period after the main occupation. The refurbished huts within D&/ucathair and D&/un Chonch&/uir appear to be contemporary with the final development of the defences at each site. They may also be contemporary with each other Ð both consist of a complex of conjoined 'cloch&/an type' structures, with possible entrance passages and featureless doorways. The ruined foundations of a second group of huts are visible along the exposed western edge of the promontory at D&/ucathair. The rectangular ground plan with rounded internal corners is typical of a number of the cloch&/ans which survive on Inis M&/or Ð well preserved examples include two cloch&/ans near Eoghanacht church and Cloch&/an na Carraige near the village of Cill Mhuirbhigh.

D&/un Aonghasa

D&/un Aonghasa is dramatically located at the edge of steep cliffs which form a more or less continuous band along the southern coast of Inis M&/or. The site commands a spectacular view from Connemara on the north to the cliffs of Moher on the east and, on a clear day, Mt. Brandon on the Dingle Peninsula can be seen on the skyline to the south.

The cliff-top location and the complexity of its defences link D&/un Aonghasa with the hillfort tradition. About fifty hillforts have been recognised to date in Ireland, and most are generally considered to have been built in the Iron Age. Intensive study of hillforts in Britain has indicated a complex development from Late Bronze Age beginning down to the end of the first millennium BC or early centuries AD.

The substantial inner citadel at D&/un Aonghasa also links this site with the ringfort tradition and therefore the monument, as it survives today, probably incorporates alterations and refurbishments carried out at intervals over a long period of time Ð perhaps as long as a thousand years.

There are three main enclosing walls, each terminating at the cliff edge along the south. An additional wall in the west sector now appears to begin and end abruptly. The walls are of drystone construction and were terraced on the interior face; steps leading up to the terraces survive on the inner two walls. The broad band of chevaux de frise outside the middle enclosure is up to 38m wide in places and still proves a formidiable obstacle today, with individual pillarstones standing up to 1.75m in height.

The three main walls subdivide the interior into areas of quite separate character. Much of the outer enclosure is characterised by steeply falling ground and areas of bare weathered limestone. The inhospitable exposed terrain, and the location of the chevaux de frise along its inward perimeter, suggest that this area may have been used mainly for animals. In contrast, the middle enclosure affords some protection from the prevailing winds and consists of fairly level ground, with some soil cover. A number of possible hut sites have been identified here in the course of recent fieldwork.

The inner enclosure surrounded on three sides by a massive wall up to 4.9m in height and 5.8m in thickness, is elevated above the remainder of the fort. There are two terraces on the interior of the wall and there is some evidence to suggest that the inner terrace was a later addition. The entrance to the inner enclosure is through a monumental gateway in the north-east, but a chamber in the wall on the west side may be an earlier blocked-up entrance. It is likely that some protective walling existed along the cliff edge during the occupation of the site. The interior is level, broken only by a platform of bedrock at the cliff edge. It has been suggested that this platform formed the focus of ritual activity during the Iron Age. The rock was certainly left in place deliberately and its present table-like appearance is not completely natural, but there is no way of knowing now whether or not it had a special significance for the builders of the fort.

Excavation

Two seasons of excavation have now been completed at D&/un Aonghasa and a further season is planned for the coming summer. Most of the excavation to date has been concentrated in the western half of the inner enclosure. Here, the remains of a number of hut sites have been uncovered. The best preserved example is roughly circular in plan and 4.8m in diameter. The walls were formed of low orthostats and there was an entrance in the east side. The western edge of the hut now lies under the lower terrace of the inner enclosure wall. It seems unlikely that the single slabs which made up the wall could have formed the foundations of a cloch&/an-type dwelling and the superstructure may, therefore, have been of wood.

The interior of the hut had a paved floor and there was a stone-lined hearth. The occupation layer overlying the floor contained limpet shells and a few periwinkle shells, sheep, cattle and pig bones and a small number of guillemot bones. Finds included coarse pottery, mainly from bucket-shaped vessels used for cooking, part of a clay mould for casting a bronze spearhead, two crucible fragments and a finely carved bone pin.

A short distance outside the doorway of this hut the remains of a broadly contemporary stone-lined trough were preserved. The trough was over 1m in length, 0.6m wide and 0.35m deep, and was filled with stony clay containing animal bone. The only artefact recovered was part of a bead made from pumice. A sample of animal bone gave a date range of 752-392 cal. BC.

The exact function of this trough is difficult to determine. At Skara Brae in the Orkney Islands, similar stone troughs were found set into the floors of the Neolithic houses, and are thought to have been storage tanks for shellfish. Stone troughs also occur at fulachta fiadh, where they were used in cooking. The lack of fresh water in the immediate vicinity of D&/un Aonghasa may make this interpretation less likely, but it is possible that like the present day Aran Islanders, the occupants collected rainwater.

Both the trough and the hut overlay earlier occupation material. No definite structures associated with this earlier occupation have been found within the inner enclosure but a second cutting, opened just outside it to the north, contained the remains of a fairly crude hut. The walls of this hut were formed of irregular uprights and, along the west, the hut was butted up against the remains of a wall. A radiocarbon date from animal bone in the occupation layer gave a date of 900-450 cal. BC.
