Souterrain

The National Monuments Service's description

At the S end of Horn Head, on a gentle E-facing slope with rock outcropping adjacent at SE−S, in a broad expanse of undulating grass-covered sand hills. A bay bordered by a beach, Tramore Strand, is located 900m to SW and the estuarine bay at Dunfanaghy is c. 1km to SE.
This souterrain is not indicated on any edition of the OS 6-inch maps. It was first recorded by NMI in 1968 (SMR file).
The souterrain is of drystone construction with lintel roofing. It can be traced for a length of c. 20-21m on a roughly L-shaped plan, extending for c. 14m on an E−W axis and at the W end changing direction for c. 7m to NNW. Three constrictions/short creeps subdivide it into four separate, consecutive sections/lengths of passage: a single NNW−SSE section and three sections on the E−W axis. The individual passages vary in length from 2.3-7m. In addition, a short side passage/chamber (L 2.8m N−S; Wth 1m E−W; H 0.7), rectangular in plan, opens off the N side of the eastern-most length of passage.
There is little variation in passage width (Wth c. 0.7-1m) and height (0.7-0.9m) throughout the souterrain. Each separate length of passage is narrow and low; it is not possible to stand upright at any point and movement through the souterrain requires crouching or crawling. There is a change in level between the NNW−SSE section and the E−W section, with one length of passage in the E−W section sloping downwards markedly from W to E, reflecting the natural slope of the hill in which it is constructed. The central passage on the E−W axis curves in a gently sinuous way.
The side walls are rather roughly built in 3-5 random courses using angular stones of varying sizes; in parts, the basal course incorporates very large boulders or stones set on edge. In contrast to the side walls, the constrictions/creeps appear more carefully constructed, flanked by upright jamb stones, which project from the passage walls, and covered by low set lintels. The souterrain roof is constructed using large slabs/lintels laid horizontally. The floor is sandy earth.
It is not clear whether the current NNW and E terminals of the souterrain are original end points or merely the result of recent blockage. The location of the original entrance is also uncertain, but there are now four areas of surface subsidence or collapse. Within the souterrain, several roof lintels exhibit cracks or a degree of displacement, and further subsidence/collapse is likely.

Compiled by: Jane O’Shaughnessy

Date of revised upload: 3 February 2022