County: Offaly Site name: DERRYNAGUN BOG, Lemanaghan
Sites and Monuments Record No.: N/A Licence number: 00E0497
Author: Ellen OCarroll, ADS Ltd.
Site type: Platform - peatland
Period/Dating: Late Medieval (AD 1100-AD 1599)
ITM: E 618306m, N 727287m
Latitude, Longitude (decimal degrees): 53.295568, -7.725392
Excavations were carried out in Derrynagun Bog, Co. Offaly, as part of the Bord na Móna Archaeological Mitigation Project. These excavations were undertaken to resolve known archaeological sites so that Bord na Móna could resume peat production in areas that had been cleared of archaeology. Derrynagun Bog is to the north-east of Lemanaghan dryland island, where the site of the monastic establishment of St Manchan of Liath is reputed to have been founded in the middle of the 7th century. This excavation exposed a brushwood platform, which was one of a series of sites excavated alongside a Bord na Móna drain edge (see Excavations 2000 Nos 819–20, 821–6). The wood associated with the site had been milled on the north-western side of the cutting. It was composed of approximately 200 brushwood elements, some pegs and some interspersed twigs. The site was 2.1m wide, 3.5m long and 0.5m in depth. Most of the brushwood rods were concentrated in the centre of the cutting, arranged longitudinally, and were very straight in nature. The brushwood elements dipped towards the centre of the site and were up to three layers deep in places. To either side of the concentration, the brushwood was haphazardly placed with no particular orientation. There were four transversely placed brushwood rods; these ran underneath the longitudinal brushwood to provide support. The twigs were interspersed between the brushwood and would have filled in the gaps between the wood, providing stability to the wooden structure.
There were 36 worked ends recorded from this site. Most were chisel-pointed and single-faceted. The facets appear to have been cut with a metal axe. There were some tears recorded above the worked facets, which may indicate that the builders first tried to axe the branches off, and when this was not successful they tore the branch from the tree.
It is clear from the excavations that this site was a small, compactly lain platform, held in place with pegs and further compacted by the use of twigs within the structure. This site has been radiocarbon dated at University College Dublin to cal. AD 1332–1625 (UCD-0103). It is possible that the wood was intended to serve as a small, dry platform for hunting or other such activities. The relationship between this site and the sites located in the near vicinity will be ascertained in the post-excavation stage.
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