2006:427 - St Mary’s Church, Macosquin, Derry

An evaluation excavation was conducted in advance of a proposed graveyard extension at St Mary’s Church, Macosquin, Co. Derry. St Mary’s Church is built upon the site of the medieval Cistercian abbey of Clarus Fons (LDY007–045), which was probably founded in the year 1217 (Gwynn and Hadcock 1970, 139).
In advance of the proposed utilisation of a field to the east of St Mary’s Church as a graveyard, a geophysical survey was carried out by Dr Stephen Trick, Centre for Archaeological Fieldwork, School of Geography, Archaeology and Palaeoecology, QUB. This survey identified a number of geophysical anomalies that were potentially archaeological in nature. It was suggested by the EHS that trial-trenches be manually excavated to test these anomalies.
Three trenches were excavated: Trench 1 measured 2m by 10m, Trench 2 measured 1m by 3m and Trench 3 measured 1m by 3m. Trenches 2 and 3 were separated by a 1m baulk. During the course of the excavation, the baulk between Trenches 2 and 3 was removed to make a single trench, which measured 1m by 7m. These trenches were located so as to test geophysical anomalies detected by the geophysical survey. Trench 1 was located to test two areas of unusually high and unusually low resistance, which were interpreted by Dr Trick as possibly being archaeological features. Trenches 2 and 3 were located to test the apparent presence of a large low resistance anomaly, interpreted as a linear ditch, and a higher resistance anomaly, which was interpreted as possibly being a wall.
The excavation in Trench 1 uncovered the base of nine, apparently truncated, post-holes at the north-western end of the trench. The presence of medieval pottery in one of these post-holes indicates that they are of medieval date. At the south-eastern end of the trench there was an area of stony subsoil. There were initially thought to be archaeological features in this end of the trench but these were demonstrated, upon excavation, to be natural depressions in the subsoil that had become filled with dark, anthropogenically derived, material.
At the north-western end of Trench 2/3 there was a ditch, 3.5m wide and 0.9m deep. Its primary fill contained fragments of medieval pottery dating to the 15th to 16th centuries. The ditch was recut to accommodate an unmortared wall and was capped by topsoil.
Reference
Gwynn, A. and Hadcock, R.N., 1970 Medieval Religious Houses: Ireland. Longmans, London.