Ecclesiastical enclosure in Clonmacnoise

On top of NE-SW esker ridge overlooking Clonmacnoise and the river Shannon to the NW. Earthen bank (Wth 2m; H 0.7m) with outer fosse visible only in places traverses the top of this esker ridge and may have originally enclosed the ecclesiastical remains of Clonmacnoise as illustrated by Thomas (1971, 29-31). Possible second enclosure located further to the S (pers. comm. Donald Murphy). Archaeological excavations carried out by D. Murphy under licence no. 99E0715 prior to the construction of the tourist office at Clonmacnoise revealed evidence for the ecclesiastical enclosure, and two burials of a possible medieval female cemetery (OF005-066). An area measuring 16.65m east-west by 29.25m was excavated to the south of the existing tourist office building just north of the base of the slope of the esker ridge (Eiscir Riada). Significant archaeological features were exposed on the site, representing three distinct phases of activity. The most recent phase is characterised by the presence of cultivation furrows that run north-south through the cutting. The furrows were all roughly U-shaped, were generally evenly spaced and maintained a fairly consistent depth and width. Their alignment and consistency would indicate that they were all roughly contemporary. Near the north end, three of the furrows had associated post-holes and all three furrows were quite shallow, c. 0.05m. Nine pits were exposed cut into the natural, grey and brown sand below the cultivation furrows. These are probably roughly contemporary and, though no definitive dating evidence was recovered, are likely to post-date the infilling of the ditch (see below). Other, smaller features were exposed, including a possible stone setting, a spread of charcoal and iron slag, a linear slot-trench, a possible bowl-shaped furnace and an ash and charcoal spread. Two burials were also uncovered along the south baulk below the topsoil and cut into the natural sand. Both burials were extended female inhumations aligned east-west in simple grave-cuts. Burial 1 was that of an adult female aged between 25 and 30 years. This individual had a severe stress fracture of a vertebra and fractures to the first ribs and sternum. These may all have been caused by exerting extreme force such as was required for lifting or moving a heavy object. Although the fractures did not result in immediate death, they may have led to complications causing death a short time later. A sample of bone from the burial produced a radiocarbon age of 748±42 years BP, which gave a calibrated date range of AD 1252-78. Burial 2 was that of a female aged 35-50 years. This individual had suffered three broken ribs, possibly as a result of a blow or a falling object, and was already exhibiting signs of degenerative joint disease that would have become worse with increasing age. A sample of bone from the burial produced a radiocarbon age of 816±43 years BP, which gave a calibrated date range of AD 1182-1262. Both burials had some similar congenital abnormalities that may hint at a possible genetic link between the two. It is also possible that they lie on the northern fringes of a much larger cemetery. The burials occurred to the south of a large infilled ditch, 6.2m wide at the top and 1m wide at the bottom at the west end, and 5m wide at the top and 1.7m wide at the bottom at the east end. It was 3.7m deep at the west end and 3.8m deep at the east end. The ditch was roughly V-shaped in profile but with a flat bottom. The northern side was stepped, as was a portion of the south side in the south-west corner. There was clear evidence for slippage near the west end, where sands had slipped down into the bottom of the ditch along the northern side, indicating that perhaps there had been a bank along the north side originally. It would appear from the main fill, a sandy, grey-brown soil, that the ditch was filled in one episode rather than silting up over a long period of time. Animal bone recovered from the main fill provided a date of 1228±43 years BP, which gave a calibrated date range of AD 714-873. This would suggest that the ditch was purposely infilled during the 8th/9th century. The ditch represents an outer enclosing element of the early monastic complex. Dúchas applied to Offaly County Council for permission to install a new wastewater treatment system for the Visitor Centre at Clonmacnoise. Permission was granted for large septic tanks to the west of the existing system, with a direct outflow pipe to the Shannon. The work was to be monitored. Three test-trenches were opened under licence no. 02E1407 on the proposed location of the tanks on the crest of the esker to the north of the Visitor Centre, where limited archaeological deposits are known to exist. Trench 1 was opened in an area that had been previously disturbed by the existing sewerage system; evidence was uncovered that some archaeological features survived intact, so the location of the tanks was moved farther west (see below). During the monitoring of the excavation of the trench three pits were discovered. Further test-trenches were opened on the line of the outflow pipe, and archaeological deposits were revealed at a depth of c. 0.3m on the raised ground between the existing percolation area and the Shannon flood-plain. Excavation of the pit for the tanks, 15m by 4m, revealed that the stratigraphy comprised 0.4-0.6m of redeposited material from the demolition of the schoolmaster's house that was situated to the west of the monastic site in the 1980s. This material lay above the original sod layer and an agricultural horizon under which was a black layer that produced cut antler, iron objects, charcoal, animal bone and some slag. A fragment of a rotary quern was also recovered from this feature. A section of a small hearth containing slag was noted in the north section face. Three pits were uncovered: two on the north (downhill side) of the cutting and one on the south. One pit (F4) on the north side contained yellow brick, piping and plastic refuse from the demolition work of the 1980s, and the other two (F2 and F5) were medieval. F2 had no stratified layers and produced animal bone, an iron knife and nails, a bronze pin fragment and a bronze, collared, stud-headed pin (11th-13th century). F5 had a number of deposits, with evidence of having been open for a considerable time, and produced iron objects, cut bone and antler, lignite, a bone bead fragment, a fragment of a hone and some slag. Further excavation was necessary on the high ground to the east in the area already tested, as an extra tank was required. The only stratified feature in this area was a platform of large stones measuring c. 1m by c. 3m. It consisted of a single layer of large stones, 0.2-0.5m, with small cobbles laid between. It had been curtailed to the north and south by the existing pipes and percolation area. The layer into which these stones were laid produced a bone pin tip and a piece of cut antler. Excavation in the trench for the outflow pipe has been discontinued but to date has produced evidence of extensive ironworking, stone settings, pits and hearths, as well as a number of early medieval finds. This will be reported on after completion of the excavation in 2003. Work has currently halted owing to adverse weather conditions and the rise of the Shannon in late October/November. Heather A. King, Skidoo, Ballyboughal, Co. Dublin. Excavation of a trench under licence no. 02E1407 for an outflow pipe to the Shannon in connection with a new wastewater treatment system for the Visitor Centre at Clonmacnoise, suspended last year due to flooding, was completed in March (Excavations 2002, No. 1565). The trench for the outflow pipe was 1m wide and c. 40m in length. The northern third of the trench was in the flood-plain of the Shannon and had no archaeological material. The river end of the middle section of the trench had been built up to raise the level of the ground above the high flood level