2005:894 - LISMORE (1), Laois

Testing was carried out before the construction of the M7 Portlaoise–Castletown/M8 Portlaoise–Cullahill motorway scheme. In March 2005, during centre-line testing of Contract 2, Testing Area 8, carried out by Lydia Cagney (see No. 863, Excavations 2005), three areas of archaeological significance were identified in Field 548 (Plot 140). The site was designated Lismore 1 and was excavated between 11 October and 2 December. An area measuring 30m by 30m and two areas of 10m by 10m each were stripped of topsoil by mechanical excavator to a depth of c. 0.4m. The area initially under excavation was subsequently enlarged, incorporating the two smaller cuttings, forming an overall area of c. 75m (north–south) by c. 60m.

Excavation of the site revealed the remains of the western half of an enclosure, comprising a single ditch c. 60m in diameter, with a north-facing entrance defined by a 4m-wide break in the circuit of the ditch. The enclosure ditch measured c. 2.5m wide by up to 1m deep. The two main fill types were stony grey/brown clay and pale grey silty clay. The fills produced several animal bones and some pieces of iron slag. The finds included a copper alloy blade fragment, a green glass ring bead, a piece of cut antler and a sandstone quern fragment.

The largest feature within the enclosure was a pit measuring c. 6m long (north–south) by 2m and 1.4m deep. This feature was filled with clay deposits containing charcoal, burnt stone, burnt bone and iron slag, and also produced a small sharpening stone, an unusual polished stone with a single slash mark on each face, an iron knife and an iron ring. Other features in the enclosure were randomly dispersed pits and post-holes, which did not appear to be structurally coherent on plan.

The site is the levelled remains of a univallate ringfort, characteristic of the early medieval period, most likely dating from the 7th–9th centuries.

Unit 21, Boyne Business Park, Greenhills, Drogheda, Co. Louth