Megalithic tomb - wedge tomb

The National Monuments Service's description

In mountainous, blanket bog-covered terrain, located on a natural elevation at the NE end of Lough Mourne. The location provides views towards Barnesmore Gap, an important natural routeway through the Blue Stack Mountains, which lies c. 5km to SE. The wedge tomb was constructed immediately to SW of a Neolithic cairn (DG086-002001-).
This wedge tomb was discovered in 2011 during an archaeological excavation at the cairn carried out in advance of the proposed development of a dam at Lough Mourne; the tomb was fully excavated (Delaney 2013).
The wedge tomb (total L c. 8.5-9m; Wth façade c. 4.5-5m) consisted of a wedge-shaped gallery (L 5.2m; Wth c. 2m at entrance, 1m at rear) outlined by a double wall of orthostats or upright slabs, with the entrance at the broad end facing WSW. The tomb had suffered disturbance in the past: There were no in situ roof stones, and the tops of several orthostats in the inner wall had been smashed. The excavation revealed that the tomb was constructed on a deliberately levelled surface, consisting of a cut terrace. The stones of the inner gallery wall, were erected directly on this surface, and were not placed in dug sockets. The N and S long sides of the gallery were originally each defined by five orthostats, the front facade consisted of two large triangular uprights, and a single upright closed the back of the gallery. A consolidating layer of clay and stones was laid down to hold the inner gallery wall in place. This was followed by the construction of the outer gallery wall, at a distance of c. 1m from the inner wall; this, in turn, was consolidated by further deposits of stony packing material. A deposit of white sand, probably derived from the lake shore, was found within the gallery, and appeared to represent a deliberately laid surface or floor. Oak dominated the charcoal fragments recovered from this floor level. Oak wood may have been deliberately chosen, as it has been noted that it is the wood type most commonly used as fuel in fires for prehistoric burial or cremation rituals in Ireland (Delaney 2013, Appendix 2.2, E. O’Carroll; Grogan et al. 2007, 107-114). A sample of charcoal from this layer returned a C14 date of 2458-2205 BC (UBA 19996) (calibrated to 2 sigma), indicating activity in the early Bronze Age. A number of Neolithic flint artefacts, including a rare petit tranchet derivative, were recovered from levels underlying the tomb, but no artefacts or evidence of burials were found within the tomb. (Delaney 2013, 13-17).
The excavation uncovered a number of other monuments in close proximity to the Neolithic cairn (DG086-002001-) and this early Bronze Age wedge tomb: a burnt spread (DG086-002005-) and a pit (DG086-002006-), both dated to the middle Bronze Age, and a fulacht fia (DG086-002007-) dated to the Late Bronze Age, all indicating that this location was an important focus of activity for a period spanning a millennia.

Compiled by: Jane O'Shaughnessy

Date of upload: 16 January 2018

References

Delaney, S. 2013 Final report of an archaeological excavation undertaken at Lough Mourne, Co. Donegal. For URS, on behalf of Donegal County Council. Licence no. 10E0309, 10R0103. April 2013. Unpublished report submitted to National Monuments Service.