2003:376 - GRANGEMORE DUNES, Grange More, Derry

Five sites of archaeological activity were identified within a confined area of 2.8ha in the Grangemore sand-dune system, Co. Derry, by the Centre for Maritime Archaeology, University of Ulster, during its archaeological survey of the north coast. The sites were exposed as a result of cattle grazing and were immediately threatened by on-going activity. An excavation was undertaken by the Centre for Archaeological Fieldwork in August for a period of one week, during which time Sites 1 and 5 were investigated. Permission to excavate Sites 2, 3 and 4, located in an Area of Special Scientific Interest comprising the northern part of the dune system, had not been obtained by the time of the excavation. Exploration of these sites was therefore limited to a survey of their locations and a record of their heights. Finds were examined by Dr Eiméar Nelis (flint) and Ms Sarah Gormley (pottery), Queen’s University Belfast; the archaeobotanical remains were examined by the author.

Site 1 consisted of a stone setting exposed in the section of a dune blow-out and associated with a 0.26m-deep soil horizon, at a level of 7.8m OD. The overlying sand deposit was excavated down to the stone setting within an L-shaped area extending 2.2m to the north and 0.7m to the east of the feature. The stones were set irregularly, up to four deep, largely within an area c. 0.3m in diameter. The lowermost stones, in contrast, lay with a flat surface turned up, in a bowl-shaped depression that cut into the underlying, wind-blown sand deposit. Four sherds of plain, nondescript pottery were recovered from within the feature and a small deposit of fine, humic soil occurred between the stones. Evidence for in situ burning was not apparent. A charcoal fragment from the humic soil was AMS radiocarbon dated to 1950–1740 cal. BC (UB-6275, 3512±37 BP), placing the site within the Early Bronze Age. Eight pieces of undiagnostic flint flake debitage were recovered from the soil horizon north of the feature and a soil sample produced the remains of two charred cereal grains. No further archaeological remains were noted. The cereal grains were AMS radiocarbon dated to cal. AD 1160–1280 (824±27 BP, UB-6146), suggesting that the soil horizon formed in the medieval period, probably after one or more periods of sand erosion had denuded the Early Bronze Age stone setting. The cereal grains testify to a second phase of human activity on the dunes.

Site 5 comprised a scatter of burnt stone, pottery (including possible everted-rim ware), largely undiagnostic flints and World War Two bullets at the base of the dune. The material was ex situ, presumably eroded from a higher soil horizon visible in the marginal face of the dune across a length of 15m. Investigation of the site therefore concentrated on this horizon and entailed the opening of two trenches 2.5m apart. Trench 1 measured 1m by 1m. Excavation revealed a 0.5m-deep buried soil horizon stratified within deposits of eluvial sand. Charcoal flecks were evident through the soil horizon, but evidence for archaeological activity was lacking. Macrobotanical investigations of samples from this layer, however, led to the recovery of charred barley, oat and rye grains, indicating human activity in the vicinity. Grains from the upper unit of the soil horizon have been AMS radiocarbon dated to cal. AD 1490–1660 (302±32 BP, UB-6145). This date overlaps with the date range for everted-rim ware, supporting the supposition that some of the finds at the base of the dune eroded from this horizon. Trench 2 (0.75m by 1m) was opened to the north of Trench 1 but, similarly, revealed no archaeological remains. The exposed soil horizon was examined visually along the length of the dune, but archaeological material was not noted.

Site 2 was the most substantial of the sites exposed, with evidence for burnt stone, flint and pottery in situ in the base of a dune blow-out 86m to the north-east of Site 1. The site lay at a level of 8.5m OD. Sites 3 and 4, 120m and 170m to the west of Site 5, consisted of spreads of burnt stone, prehistoric, medieval and post-medieval (17th-century North Devon gravel-tempered ware) pottery, flint (including a possible scraper at Site 3) and slag. The finds were ex situ at a height of c. 5m OD, but their provenance was not identified.

School of Archaeology & Palaeoecology, Queen’s University, Belfast BT7 1NN