2006:1639 - SLANE, Meath

Preliminary testing of geophysical anomalies identified during a survey of the proposed route for the Slane bypass was undertaken in May 2006. The survey was carried out as part of the environmental impact assessment of the route. Geophysical survey of Areas 10 and 11 in Slane townland identified a number of anomalies indicating possible enclosures. This assessment was designed to test the geophysical results and to determine the depth and extent of any archaeological features encountered.

Area 10 contained a geophysical anomaly, suggesting a large rectangular enclosure some 50m in north–south diameter, which did not feature on the first-edition (1836) OS map. The enclosure was on a gradual north-facing slope and its eastern limit was defined by the townland boundary between Slane and Cashel townlands. Five trenches were excavated to assess this enclosure. The enclosure ditch was revealed in Trenches 1–3 and was sectioned in the two former trenches.

The ditch measured 3–3.5m in width and was up to 1.4m in depth. The basal deposit was greyish-brown silty sandy clay that contained sparse flecks of charcoal with relatively few stones and moderate amounts of animal bone, which was in poor condition. The deposit contained a lens of grey silty plastic clay with moderate amounts of animal bone. This was overlain by mid-brown silty sandy clay with few inclusions. The upper deposit was marked by dark-brown silty clay with frequent charcoal flecks.

No artefacts were recovered and the ditch contained largely poorly preserved animal bone. A linear gully, possibly contemporary with the main enclosure ditch, was excavated in Trench 1. This contained charred plant remains consisting of wheat, oat and barley. The interior contained relatively few features. Trench 5 contained a shallow pit with dark deposits containing animal bone and charcoal-rich soil which included cereal remains. The animal bone assemblage was small and included cattle and horse. A cow atlas from the enclosure ditch was dated to 660–820 cal AD (UB-7240). The rectangular enclosure in Area 10 is probably related to settlement remains, indicated by the animal bone found within. The proposed route will impact on the enclosure.

Area 11, to the south of Area 10, contained anomalies suggesting a potential circular enclosure associated with a series of linear features. The trenching of Area 11 did not confirm the presence of archaeological features corresponding with the geophysical anomaly. They uncovered outcropping bedrock in the north of Area 11, which may possibly account for the geophysical anomalies. However, these trenches only sampled a small part of the area covered by the anomalies and it was recommended that further investigations take place in Area 11 prior to road construction to further assess the geophysical survey results in this area.