2002:1948 - BALLYNABARNY, Wicklow

Testing was carried out by Eoin Halpin in October 2001 at Ballynabarny, Co. Wicklow, before construction of the N11 Newtownmountkennedy–Ballynabarny Road Scheme (Excavations 2001, No. 1333, 01E0971).

A number of spreads were identified. Three of these, all of which contained deposits of heat-shattered stone, were excavated in February 2002. The first two contained mid-sized mounds of charcoal and material rich in heat-shattered stone and an assortment of subsoil-cut features, including typical burnt-mound troughs. The third area, which was truncated to the north by a small stream that had been widened by machine in modern times, survived as a small spread of burnt-mound material with no associated subsoil-cut features.

Area 1 contained a semicircular mound that was cut to the north by the widened stream. The surviving mound measured 8.7m east–west by 5.6m. The original extent of the mound, which had a maximum depth of 0.39m after the removal of topsoil, is unknown but is unlikely to have exceeded 11m north–south (i.e. to have reached the northern side of the widened stream). Other than the disturbance caused by a series of stone-filled land drains and the stream to the north, the mound appeared to be largely unaffected by post-depositional factors.

It overlay a number of depressions or subsoil-cut features, all of which were filled with material that was slightly less stony than the burnt-mound material above them. It is possible that these features represent the sockets of stones or rocks, which were removed in antiquity.

A second series of features was revealed outside the limits of the burnt mound. One of these, a rectangular cut measuring 2.2m by 1.2m, was excavated 1.5m from the south-western limit of the burnt mound. It had straight sides, a flat base and a post-hole set in each corner and clearly functioned as a trough. It had a maximum surviving depth of 0.38m and contained the fragmentary remains of a timber lining along its southern, eastern and northern edges. In addition, faint depressions in its level base appeared to represent narrow roundwood timbers oriented along its long axis. The fills were largely composed of heat-shattered stone in a variety of charcoal-rich, silty soils.

Area 2 was upslope from Areas 1 and 3, away from the stream that ran beside the other mounds. The water source necessary for the use of the trough may have been provided by the ancestor of a freshwater spring that flowed freely during the excavation. This spring was c. 9m south-west of the possible troughs described below.

In common with Area 1, Area 2 was characterised by a mound of heat-shattered stone. The mound, which was roughly subrectangular, measured 10.15m east–west by 4.7 and was a maximum of 0.25m deep. The original extent of the mound, which was disturbed by agricultural drainage, is unknown, but it is unlikely to have far exceeded the recorded measurements.

The burnt-mound material extended to the south-east as a shallow spread. This material, which overlay a number of archaeological features, may have been dragged across the site by modern ploughing and during the excavation of a series of stone-filled drains that criss-crossed these areas.

The morphology of the features excavated in the vicinity of the burnt mound, which were largely filled with deposits containing heat-shattered stone and charcoal, varied. Immediately to the north of the mound a shallow elongated cut was associated with three stake-holes.

Two features that appeared to have functioned as troughs were excavated immediately to the south-west of the mound. These features were within 0.4m of each other and were overlain by a shallow spread of burnt-mound material. Both were roughly rectangular. The smaller feature measured 1.74m by 1.08m; its sides sloped gradually to sharply to a flat base at a depth of 0.25m. The larger measured 2.8m by 1.8m and was 0.5m deep. The cut was partially surrounded by large granite boulders. Elsewhere along the generally sheer sides of the cut, what appeared to be large rock sockets were filled by burnt-mound material. This burnt-mound material filled the entire cut. A series of four large stake-holes/small post-holes was excavated at the corners of the trough. The timbers represented by these stake-holes may have supported a timber lining of the trough, no other trace of which survived.

One linear feature was recorded, interpreted as a post-medieval field boundary. It was a maximum of 1.21m wide and was recorded along an interrupted north–south line, right across the site, for a length of 21m. It was 0.05–0.29m deep; its base appeared to slope down the hill from south to north, and the greatest depth was reached at the northern limit of excavation. The cut was filled by a loose grey silt typical of basal ditch fills. To the north of the mound this silt was overlain by a similar but darker material, which contained frequent heat-shattered stone. Its interpretation as a field boundary is placed in doubt by a 10.5m interruption in its length. The causeway, which appeared too wide for an agricultural field boundary, was centred on the surviving burnt mound. The coincidental placement of a field entrance over an earlier burnt mound appears unlikely. It is possible, however, that the location of a later gateway or entrance took advantage of the firm ground provided by the mound of heat-shattered stone in an otherwise boggy area.

In common with Area 1, Area 3 was immediately to the south of the modern drainage ditch/small stream. Unlike the mounds excavated in Areas 1 and 2, the archaeology uncovered at Area 3 took the form of a small spread of heat-shattered stone in a charcoal-rich but otherwise friable soil. This deposit was cut to the north by the drainage ditch and may not represent an in situ burnt-mound deposit. It measured 8.15m east–west by 1.75m, with a maximum depth of 0.12m. A second, shallower deposit of heat-shattered stone extended 3.65m to the south. It contained very little charcoal and was only 0.01–0.05m deep; it appeared to have been washed clean of its charcoal inclusions over time. This lack of charcoal, coupled with the loose, soily nature of the first deposit, may suggest that the material excavated at Area 3 was largely ex situ and had been disturbed and redeposited during the modern mechanical excavation of the drainage ditch to the north.

Windsor House, 11 Fairview Strand, Fairview, Dublin 3