Man-made underground passage in Benagh

The following description is derived from both the published 'Archaeological Inventory of County Louth' (Dublin: Stationery Office, 1986) and the 'Archaeological Survey of County Louth' (Dublin: Stationery Office, 1991). In certain instances the entries have been revised and updated in the light of recent research. Date of upload/revision: 17 July 2007 Discovered during the course of land reclamation in 1985. This work involved the removal of an inland promontory fort (LH008-051001-) at which there was tradition of a Man-made underground passage (Buckley 1986a, 38). Bulldozing and grading of the area displaced a capstone of one of the beehive chambers in the Man-made underground passage. Present access to the site is via the gap left by the displaced capstone. The Man-made underground passage consists of a series of passages and chambers roughly aligned NW-SE, with a beehive chamber (diam. 2.5m, H 1.6m) at its NW end with a passage leading off SE. Between the passage and the beehive chamber is a constriction (L 0.7m, Wth 0.7m, H 1m) also aligned NW-SE. Passage 1 (L 6.5m, Wth 0.9m, H 1.2m) continues SE and ends in a second constriction (L 1m, Wth 0.6m, H 0.6m). This widens out to form passage 2 (L 6.5m, Wth 0.9m, H 1.2m) which continues on to the SE. In the middle of the N wall of Passage 2 is a creep giving access to Passage 3 which leads to the NNE. Passage 3 (L 3.5m, Wth 1m, H 1m) is blocked by collapse at the NNE and is probably close to the position of the original entrance. At a point 1.5m from the SE end of Passage 2 is a drop-hole creep (dims.0.5m x 0.6m, D 0.75m) which gives access to Passage 4 at a lower level. Passage 4 (L 6m, Wth 0.7m, H 1m) extends WNW-ESE and terminates in a second beehive chamber (diam. 2.1m, H 1.7m). At floor level in the SE quadrant of this chamber is a stone-lined drain which extends SE for 3.5m then curves out of sight. At this point the Man-made underground passage is at the level of the two small streams which meet below the promontory fort, and thus the need for an effective drain. The Man-made underground passage was drystone-built throughout. The construction trench (Wth 2m) of the Man-made underground passage was noted in 1985, giving an outline of the direction of the Man-made underground passage visible as hard-packed greysoil and rubble against the surrounding yellow boulder clay. Several sherds of Man-made underground passage ware were found in its fill. This monument is subject to a preservation order made under the National Monuments Acts 1930 to 2014 (PO no. 8/1985). See the attached view of the entrance.