Dermot and Grania's Bed — Lackaghatermon

This monument is on a slight terrace on gently rising ground beside an expanse of bog above the basin of Lough Machugh. Less than 100m to the W the ground rises to a low ridge where outcropping rock breaks the bog cover. The site is 4.8km WNW of the village of Glenties and 2km S of Gweebarra Bay. Toward the E is a view along a boggy valley across Lough Ananima to the mountains beyond Glenties. The monument, considerably ruined, consists of the remains of a chamber that opened toward the SSE. It stands in a bog-grown mound that can be traced around much of the structure, although its outline is vague at the W, where it is obscured by a rectangular drystone enclosure that incorporates the remains of the tomb as its eastern side. This drystone structure, now ruined almost to ground level, measures 4.5m N-S by 7m E-W. It served as a sheephouse in the mid-19th century (Fagan 1845-8). The mound, subcircular in outline, measures 10.5m N-S by 11.5m E-W by at least 0.5m high. A fall in ground level gives the E side of the cairn an appearance of exaggerated height. The backstone of the chamber, at the NNW, and a sidestone set askew to its eastern end remain undisturbed. Approximately 1.7m S of the E end of the backstone the stump of the eastern portal-stone remains in place, but the greater part of this stone, broken from its base, leans against the opposite portal-stone, which is pitched westward against the wall of the ruined sheephouse. Immediately N of the stump of the eastern portal-stone is a prostrate slab measuring 1.6m by 0.9m by 0.3m thick. Both of these stones now support a great leaning roofstone, part of the eastern edge of which rests on the ground. This also overlies, but does not touch, the sidestone adjacent to the backstone. The chamber, when intact, would seem to have been at least 2m long. The two portal-stones, both more or less flat topped, are longitudinally set and seem to have stood c. 0.8m apart. The stump of the eastern one is 0.5m high. It leans inward slightly, a result perhaps of the collapse of the structure. Its detached portion is 1.2m long, and thus, when intact, this portal-stone would have been c. 1.7m high. The western portal-stone when upright would have stood c. 1.8m high. The surviving sidestone leans inward slightly and is 0.3m high. The outer face of the backstone is concealed by the wall of the old sheephouse. This stone is flat topped and 0.6m high. The roofstone is 3.3m long and narrows from 2.7m wide at the front to c. 1.7m at the back. It is a flattish slab and measures 0.3m in average thickness. The monument appears to have been in its present state in 1847 (Fagan 1845-8). Fagan 1845-8, book 22, 55; Crozier 1957, 66 (dolmen on slopes of Tullybeg mountain), top photograph opposite p. 120; Killanin and Duignan 1962, 295; Killanin and Duignan 1967, 297; P.J. McGill 1973 (photograph); Ó Nualláin 1983a, 32, no. 58; Ó Nualláin 1983b, 94, Donegal no. 18; SMR 1987, 74:2; Ó Nualláin 1989, 124; RMP 1995, 74:2. The above description was published in the 'Survey of the Megalithic Tombs of Ireland. Volume VI, County Donegal.' Compiled by: Eamon Cody (Dublin: Stationery Office, 2002). Date of upload: 22 September 2008 See linked document with details from Eamon Cody, Survey of the Megalithic Tombs of Ireland. Volume VI. County Donegal. (Dublin: Stationery Office, 2002)