County: Offaly Site name: LEMANAGHAN
Sites and Monuments Record No.: N/A Licence number: 98E0464
Author: Conor McDermott, Irish Archaeological Wetland Unit, Department of Archaeology, University College Dublin
Site type: Road - class 1 togher
Period/Dating: Medieval (AD 400-AD 1600)
ITM: E 616588m, N 728129m
Latitude, Longitude (decimal degrees): 53.303190, -7.751128
An excavation was carried out as part of an assessment and mitigation project in Bord na Móna's Lemanaghan Bog, Boora Works, Co. Offaly. The work was carried out between 13 October and 5 November 1998 and concentrated on a single-plank walkway and three lesser structures.
The plank walkway was first identified in 1993 during field survey carried out by the Irish Archaeological Wetland Unit, when it was traced for 454m. During the 1998 assessment the site was traced further and was finally identified as surviving intermittently over a length of 870m. The site runs in a north-south direction, and at its northern end is a zone of 25 other smaller sites to the east and west. The excavations were concentrated along a 360m length at the southernmost end of the site.
The assessment recorded visible traces of the site at fourteen locations, and nine cuttings were established. On excavation the wood in the three most southerly cuttings (Nos 1–3) proved to have been redeposited by heavy machinery. This wood was roughly aligned on the projected line of the site and represented its former presence in the general area. Cuttings 4 and 5 each produced a single in situ peg indicating the line of the site, as well as fragments of disturbed and redeposited wood. Cuttings 6–8 produced the best surviving evidence of the structure of the sites.
In each cutting the site had been truncated by Bord na Móna drains and severely damaged and partly removed by surface milling. The general pattern of construction revealed in these cuttings showed an upper surface of single longitudinal planks laid end to end supported two layers of substructure. None of the upper planks survived intact, but the excavated evidence indicates that they ranged from c. 4m to 6m long, with mortises cut through the ends, through which pegs were driven. Supporting each end of the planks was an upper substructure of single transverse roundwoods or split timbers c. 1.1m long. The lower substructure consisted of pairs of longitudinally laid timbers c. 1.5m long set c. 0.5m apart, supporting each of the upper substructural timbers. The end of each of the superstructure planks was therefore supported by three timbers and additional lesser timbers as well as supporting pegs.
Cutting 9 produced no surviving horizontally laid timbers; however, a number of pegs survived indicating a continuation of the pattern of construction identified in other cuttings.
This form of trackway construction has not been excavated before and samples submitted for dendrochronological dating provided a date of after AD 590.
Belfield, Dublin 4
