County: Armagh Site name: DRUMILLY DEMESNE, Loughgall
Sites and Monuments Record No.: N/A Licence number: —
Author: Alan Reilly, Northern Archaeological Consultancy Ltd.
Site type: Souterrain
Period/Dating: Early Medieval (AD 400-AD 1099)
ITM: E 690362m, N 851281m
Latitude, Longitude (decimal degrees): 54.402095, -6.608283
An underground passage was discovered during the construction of a new golf-course in Drumilly Demesne near Loughgall in County Armagh. Mechanical topsoil-stripping disturbed a roofing lintel of an air vent attached to the roof of the passage. This revealed a void that was found to be a drystone-lined and stone-roofed passage.
A geophysical survey was carried out by Martina McCarthy of Geoarch, within an area of c. 50m diameter of the displaced lintel. Within the same grid a 4m x 4m trench, centred on the displaced lintel, was excavated. After the geophysical results were processed it was decided to partially machine-excavate two trenches at either end of the passage.
Trench 1 revealed that the disturbed lintel had been displaced from a roughly square-sectioned, chimney-shaped air vent, built using around four layers of subrectangular stones (c. 0.4m max. dimensions) laid alternately longitudinally and traversely. These seem to have been stacked on a gap left between the lintels of the passage proper. This created a square-sectioned chimney the aperture of which had sides measuring c. 0.3–0.4m. This was encased in the stiff, orange clay.
A box-trench 1m by 2.4m within Trench 1 was excavated down a further 0.5m to the surface of the roofing lintels and the tops of the side-walls of the passage. This showed that the top of the air vent was c. 0.43m above any of the other lintels roofing the passage. The floor of the passage lay 1.54m below the top of the air vent. This implied a passage height at this point of 1.24m.
The excavated passage had been lined by drystone walling. The upper courses of the side-walls were partly corbelled, allowing the passage to be roofed by lintels, c. 0.5-0.6m wide. No finds were uncovered in any of the trenches.
The geophysical survey showed that the passage ran in a roughly south-west/north-east direction across the grid. However, the information became confused at both terminal points of the grid. In order to ascertain whether these anomalies represented structures or whether the passage terminated within the grid, two trenches were excavated in the area where the geophysics indicated that the ends of the passage were heading. Trench 2 was initially machine-excavated to a depth of c. 0.7m, without encountering the roof of the passage or a construction cut.
A narrow box-section was excavated to a deeper level. An area of this, c. 2.8m by 0.6m, was hand-excavated. This revealed that the passage continued in much the same form, orientation and dimensions indicated in Trench 1. At the roof level the passage was c. 0.5m wide, narrowing to c. 0.4m halfway down the side-walls. This may imply a slightly battered wall.
The displaced lintel and direct visual access to the passage allowed a camera to be hand-lowered into the passage. It could be seen that the passage came to a terminus c. 6m further west. Further observation showed that this appeared to be a T-junction.
Another trench, 2m wide and 10m long, was mechanically excavated in the area where the geophysics indicated that the passage reached the western side of the grid. A box-trench 0.6m wide, centred on this was excavated by a digger with a narrow bucket. One small lintel was lifted. The passage was again c. 1.3m deep, was similar in width to Trenches 1 and 2 and continued basically unchanged to the edge of the grid.
Flash photography revealed that the passage took a massive deliberate reduction in height (from c. 1.3m to c. 0.5m). It also seemed to reduce in width. This finely constructed restriction was carefully framed by a large, rectangular lintel.
The subterranean structure examined at Drumilly was a typical east Ulster souterrain. The main passage seems to have been relatively straight in plan (orientated roughly south-west/north-east) and over 40m long, making it one of the longest straight stretches of souterrain passage ever found in Ireland. There seems to have been a T-junction at the eastern end of the main passage and a dramatic, finely constructed, narrowing creep at the most westerly point visible. This narrowing may indicate that a chamber and possibly the end of the structure lie only a few metres beyond the eastern end of the grid. The chimney-type air vent is also a rare feature.
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