2008:799 - Skehacreggaun, Limerick

A large-scale excavation was carried out on a greenfield site to facilitate the construction of 147 residential units, apartments and crèche (54,347m2). The area for the development lies partially located within the zone of archaeological potential of Mungret Abbey (LI013–009). Nine specific sites were identified and excavated. These included four burnt mounds, two ring-ditches, two structures and kilns and a possible millrace. Preliminary analysis would suggest that the burnt mounds and ring-ditches belong to the Bronze Age, the structures and kilns to the 11th–13th centuries and no datable evidence was available for the possible mill-race.
Site 1 – structures and kilns
Rectangular structure
The remains of a rectangular structure were uncovered 35m to the north of the southern entrance to the development site along the centrally aligned access road. The structure measured 9.8m north–south by 5.5m (external) and was defined by an almost continuous, deeply cut but partially truncated foundation trench. The cut was U-shaped and had an average depth of 0.5m and varied in width to between 0.51m and 1.1m. The trench was filled with dark-brown lightly charcoal-flecked silty clay. The internal area measured 8.5m north–south by 3.2m and contained four post-holes and a pit with a similar charcoal-flecked silty clay fill. Seven post-holes, four stake-holes and seventeen pits were found scattered around the structure. Charcoal, animal bone, burnt bone, two bone combs, a whittle-tanged knife, bone handle and a well-preserved penannular brooch were recovered from the pits.
Corn-drying kiln (1)
A moderately preserved dumbbell-shaped kiln was found 10m to the west of the structure. The kiln was aligned north–south and had an overall length of 4.2m, a central width of 1.2m and a depth of 0.35m. The shallow bowl-shaped southern chamber had a diameter of 1.42m and a depth of 0.1m. The short flue extended into the deeper chamber at the northern end which had a diameter of 1.6m and a depth of 0.52m. The kiln was filled with dislodged limestone rubble and very little of the original stone lining remained in situ, but it did survive along the edge of the flue and around a small part of the northern chamber. The southern chamber was filled with a deposit of charcoal-rich silty clay that extended partially up the flue while the base of the northern chamber contained a shallow deposit of silty clay mixed with a small amount of animal bone.
Corn-drying kiln (2)
A second dumbbell-shaped kiln was found 2.5m to the south-east of the rectangular structure. This kiln was aligned north-east/south-west and had an overall length of 3.4m and. The north-east end was shallow, oval in shape and had an average diameter of 1.4m and a central depth of 0.26m. The interlinked nature of the two chambers meant that the central flue was largely absent but the ground level did slope from north-east to south-west. The chamber of the south-west end had a steep bowl-shaped profile 0.5m in diameter which then broadened out into a wider bowl shape with a diameter of 1.5m. The base showed clear signs of in situ burning which was surrounded by a ring of twenty tapered stake-holes with an opening on the north-east side facing the opposite chamber. This in turn was surrounded by several medium-sized stones set against a deposit of clay which were positioned around the upper broader part of the chamber. The central fill consisted of charcoal-rich silty clay mixed with traces of oxidised clay over which lay a similar deposit but with less charcoal that extended into the upper chamber. A small quantity of animal bone was recovered from this fill, but no datable material. The remainder of the kiln was filled with an ordinary build-up of silts and clays.
Stone structure 1
The poorly preserved remains of a stone building were found 9m to the north-east of the rectangular structure. The surviving portion of the building consisted of the east wall (L. 4.4m) and sections of the north and south walls (L. 4.2m and 1.9m). Only the lowest course of the wall remained in situ, which survived to a height of just 0.2–0.35m. The wall was 1m wide. The wall was built from large flat limestone slabs between 0.4–1.15m in length. Smaller stones were used to fill in the gaps. No entrance was visible. The foundations were left in situ. The internal area measured 4.6m north–south by 4.2m and contained four post-holes and eight pits.
Stone structure 2
The extremely fragmentary remains of the corner of a second building were found several metres to the east of the principal stone building under a large quantity of stone rubble and dark silty clay from which six fragments of a decorated single-sided bone were recovered. Only the foundation course survived to a height of 0.3m. The west wall measured 4.1m in length, 1m wide and was built using large flat limestone slabs with small stone insertions. The north wall was just 2.8m in length. These features were not fully excavated but left in situ. A large number of rubbish pits were found to the west of the stone structure. These pits were subrectangular in shape, 1–2m in length and had an average depth of 0.3m. The pits were filled with dark-grey charcoal-flecked silty clay from which animal bone, burnt bone, worked bone, iron slag, shell fragments and a small amount of burnt stone were recovered. A decorated and polished bone pin, a single-sided composite bone comb and a whittle-tanged knife were recovered from one pit. Two fragments of another single-sided composite bone comb were found in a second pit.
Site 2 – burnt mound
The reasonably well-preserved remains of a burnt mound were uncovered slightly to the north of the main central area of the site just as the ground level started to rise above the low-lying poorly drained areas along the stream. The mound appeared as a very low grass area, roughly oval in plan, with overall dimensions of 15.6m east–west by 9.4m. It averaged just 0.35m in height. The principal features included the characteristic mound, a trough, numerous pits and scattered post-holes. The trough was located towards the centre of the site. The roughly rectangular-shaped pit measured 2.8m north-east/south-west by 1.45m and had an average depth of 0.28m. The sides were steep and broke gradually to a flat but uneven base. The fill of the pit largely consisted of dark-grey charcoal-flecked clayey silt with heat-cracked stone. No timbers survived in the trough but eight stake-holes, two in each corner, were found. The stake-holes (diameter 0.08, depth 0.08–0.11m) were circular or oval with tapered profiles and were filled with the same dark-grey charcoal-flecked clayey silt. A cluster of pits was found 10m to the north of the trough, each containing charcoal-flecked silty clay and occasional fragments of animal bone.
Site 3 – burnt mound
This site measured 25m east–west by 8m and was uncovered during topsoil-stripping in an area north of the central stream and close to the western boundary of the development. The site was characterised by shallow deposits of burnt and unburnt stone, mixed deposits of charcoal-flecked silts and clays, a trough and several associated pits and post-holes. The large accumulation of heat-cracked stones commonly associated with fulachta fiadh or burnt mounds was absent. The centrally located square-shaped trough had a funnel-shaped profile partially cut through the underlying limestone bedrock. The upper portion measured 3.8m north–south by 3.05m, which tapered steeply down to a rectangular cut 0.45m by 0.55m. The total depth was 1.45m. The east and west sides of the trough were formed by large rounded boulders protruding from the surrounding clay and the underlying upright slabs of limestone. The north and south sides were created by simply cutting into the clay. Essentially this created a small rock pool fed by an underground natural spring which still provided a considerable amount of water. The remaining features consisted of a few pits scattered around the trough and filled with heat-cracked stones. No finds were recovered.
Site 4 – burnt mound
The remains of a large spread of burnt and unburnt stone were found during topsoil removal to the south of the stream. There were no obvious signs of a low mound prior to excavation. The area measured 25m east–west by 14m and extended outside the limits of the excavation to the south. As the area was not affected by this phase of construction works, it was decided to re-cover the site under a layer of geotextile and topsoil and preserve the remains for future investigation.
Site 5 – burnt mound
The remains of a large spread of burnt and unburnt stone were found during topsoil removal in the adjacent field to the west. There were no obvious signs of a low mound prior to excavation. The area measured 15m east–west by 6m and extended outside the limits of the excavation. As the area was not affected by this phase of construction works, it was decided to re-cover the site under a layer of geotextile and topsoil and preserve the remains for future investigation.
Site 6 – ring-ditch
The remains of partially preserved circular structure were uncovered on a flat low-lying area close to the centre of the site to the north of the main stream. Approximately two-thirds of the structure survived, the remainder was truncated by the later mill-race and by a series of plough furrows and modern drains. The surviving portion of the structure measured 13m east–west by 14m and was defined by a single concentric ditch cut into the underlying natural clay. There was no trace of a bank and no evidence for an entrance, although the entrance may have been in the destroyed south-west quadrant of the structure. The enclosing ditch was quite irregular and uneven, but in general it had a broad U- to V-shaped profile, 0.38–1.3m wide and 0.22–0.35m in depth. The western section was deeper and more regular than the eastern section which was shallow and poorly defined. The enclosing ditch contained twelve deposits of silts, sands and clays mixed with a small quantity of charcoal. The internal area of the structure was relatively flat and measured 11.1m east–west by 11.5m. A single slightly irregular tear-dropped shaped pit was located in the north-east corner, but was unfortunately bisected by a modern drain. The pit had an overall length of 1.82m. The more easterly bowl-shaped end had a diameter of 1.25m and a central depth of 0.22m. There was clear evidence of in situ burning within the cut as the base and sides were scorched a reddish-orange.
Site 7 – ring-ditch
The remains of a partially preserved ring-ditch were uncovered on a flat low-lying area in the centre of the site close to the southern edge of the stream. The northern edge of the structure had been gradually eroded by the slow meandering changes of the watercourse. Further damage was caused during the construction of the mill-race and by later agricultural activity. The surviving two thirds of the site measured 10.5m east–west by 11.5m and was defined by a single concentric ditch cut into the underlying natural clay. There was no trace of a bank. The entrance to the structure was formed by an uncut causeway 2.1m in width and facing west. The enclosing ditch was shallow, with a broad U-shaped profile 0.28–0.95m wide and 0.05–0.09m in depth. The ditch contained two fills, the lower of which consisted of soft, lightly charcoal-flecked grey/blue clay and the upper of dark-grey silty clay with occasional small stones. The internal area of the structure was relatively flat and measured 9.55m east–west by 9.35m. A single pit was located towards the centre. The pit was roughly oval with a bowl-shaped profile (L. 0.9m, W. 0.73m, D. 0.18m). The sides and base of the pit showed clear signs of in situ burning. No finds were recovered from the pit.
Site 8 – possible mill-race
The remains of a probable tail-race of a mill aligned east–west extended across the central area of the site along the northern side of the main stream. The exposed section measured 128m and truncated the two possible ring-ditches further to the west. The remainder was outside the limits of the excavation but a preliminary investigation of the unexcavated section suggested it linked up with the stream. The eastern end was truncated by the north–south-aligned stone wall and path leading from Templemungret to Mungret abbey.
The cut for the tail-race had a broad U-shaped profile with an average width of 2.2–3.35m and depth of 0.93m. The extreme eastern end was slightly funnel shaped, created and enhanced by constructing a 9.5m section neatly lined with large slabs of cut limestone. A large quantity of stone rubble had to be removed first to expose the base slabs before each side was revetted with between two and five courses of roughly hewn stone. The stone survived to a maximum height of 0.98m. The size of the stones varied considerably from 0.4–1m in length. Evidence of later repair work was visible along a 1m-section of the northern side. The section closest to the wall was badly damaged during the latter’s construction. Three stone steps, cut into the surrounding clay along the southern side, provided access down into the base of the tail-race.
During the removal of collapsed stone rubble from the waterlogged eastern end of the tail-race, several timbers were found. Two long wooden stakes, one on each side of the tail-race 1.5m from the eastern end, were positioned between the base and side wall and driven deeply into the underlying clay. A third timber lay horizontally across the tail-race resting just over the two stakes but was not firmly fixed in place by them. This long rectangular timber, which had partially spilt down the middle, had three to four perforated holes spaced 0.2m apart along half of its length. There was a suggestion of additional holes were the timber had split but due to the poor level of preservation further analysis will be required. All three timbers were sealed within a deposit of compact dark-grey silty clay that contained small shell fragments.