2000:0808 - KILLAUN BOG, Clonbeale More, Offaly

This five-week excavation formed part of the process of the mitigation of archaeological sites in the industrial peatland of Killaun Bog, Co. Offaly, where sites were already known to exist. This work was carried out on behalf of Dúchas The Heritage Service by ADS Ltd. The site was a brushwood and roundwood togher traced for over 180m across the bog. It had previously been dated to 1030–1277 cal. AD. It was c. 2.97m wide and is 0.4–0.9m below the field surface. In total, 35m of the togher was excavated at four locations. The site was initially recorded as a ‘compact brushwood and roundwood togher composed of longitudinally laid elements’ (IAWU 1998). Excavation revealed that, while its construction pattern varied along its length, it was, in fact, composed mainly of transversely laid elements.

Three of the excavated cuttings (1, 2 and 4) were 10m long by 4m wide, while the south-eastern cutting (Cutting 3) was reduced to 5m in length owing to the depth of peat cover over the site at that location. The cuttings were placed so that they were bisected by the drainage ditches. Cutting 1 was placed 70m from the northern side of the bog. The orientation of the elements exposed in section in the drain face appeared to be mainly longitudinal, running north-north-west/south-south-east, along the line of the site. Excavation revealed that the upper surface of the track was composed of 88 transversely laid brushwoods and roundwoods. These transverses ranged from 11mm to 75mm in diameter and from 0.26m to 1.34m in length, forming a total width of 1.06–2.04m. The elements were tightly placed, some overlapping, towards the central portion of the cutting, while the northern and southern extents were more dispersed. Some of the elements (29 in total) had chisel-point toolmarks at one or both ends, while six of these had evidence for branch trimming. The elements were irregularly shaped and were quite curved or branchlike; although some had traces of intact bark present, most were in poor condition. The southern extent of the cutting contained larger, more irregularly shaped elements that may have been disturbed or be the result of repair work.

The substructure of the togher was 0.05–0.2m deep and was composed of over 300 brushwood rods that were in moderate to good condition. The element orientation in this layer was approximately 80% transverse, 15% irregular and pegs and 5% longitudinal. The transverse elements were considerably smaller and less closely packed than those from the walking surface. The longitudinal and peg elements were mainly located along the sides of the togher, delineating the line of the site as well as keeping the edges stable.

The second cutting was 40m from northern edge of the bog. The drain face sighting at this location was less substantial than the material exposed at most of the other sightings. The majority of the elements exposed did not appear to be in situ and may have been displaced by the ditch-cutting machinery. The structure exposed in this cutting proved to be a lot more insubstantial than in Cutting 1. The elements ranged from 10mm to 35mm in diameter and from 0.04m to 0.2m in length, and most were in moderate condition. The orientation was very haphazard, with the majority of the elements irregularly placed with some small pegs throughout. Only thirteen of the total 175 elements had evidence for woodworking, mostly single-faceted chisel-points. Only two elements showed evidence for branch trimming. The cutting was cleaned back again, revealing a further 200 elements similar in orientation and composition to the layer above. The structure revealed in this cutting appears very different to that in Cutting 1 and subsequently in the following two cuttings. It is possible that, while it appears to follow the line of the togher, it is, in fact, another site altogether. It may be associated with the construction of the togher or may have been directly associated with a small ‘pool’ or wetter area that was exposed in the north-western corner of this cutting.

The third cutting was placed at the southernmost sighting recorded in 1998, which was 180m from the northern edge of the bog. There was a 2.5m-wide stretch of dense brushwoods and roundwoods exposed in section in the drain face, 0.3–0.5m below the field surface. This cutting was actually in the centre of the bog, as there is a large expanse of undisturbed bog to the south. This appears to have remained in private ownership. Following discussions with Dúchas, only the southern half of this cutting was excavated. The opposing field, on the northern side of the cutting, was 0.4m higher. This part of the site, as a result, was 0.7–0.9m below the field surface and therefore will not be under threat for a number of years to come.

The togher’s construction at this location was similar to that exposed in Cutting 1 but appears to have been somewhat disturbed at the southern extent of the cutting. The elements are not as densely placed as those in Cutting 1, although the construction appears to be very similar. The width of the site varied from 1.8m to 3.2m at this location. The elements were approximately as follows: 70% brushwood, 20% roundwood and 10% twigs. The roundwoods ranged from 60mm to 72mm in diameter; the brushwoods averaged 30mm in diameter; and the twigs were all under 10mm in diameter, most having bark present. Most of the elements were transversely laid, with some longitudinal elements. A leather shoe was found 1.1m from the eastern side of the togher. It was discovered toe upwards at a 50° angle. The sole was no longer attached to the upper part of the shoe. It has since been conserved.

The substructure in this cutting was quite substantial compared with the dispersed nature of the superstructure. This was very similar to the substructure in Cutting 1 and varied in width from 1.8m to 3.4m. It was composed of transverse, irregular and longitudinal brushwoods and roundwoods, with some brushwood pegs particularly around the sides of the togher. Again the southern extent of the cutting contained less material. The elements ranged from 15mm to 110mm in diameter and were generally in better condition than those from the layer above.

The final cutting was placed 138m from the northern side of the bog and 28m north of Cutting 3. The section already exposed in the drain face here did not look any different to the others. It was composed of several brushwoods and roundwoods, visible on both sides of the drain, spread over an area 2.5–2.8m wide. Over 375 elements were exposed in the first cleaning of this cutting; over 100 of these had evidence for woodworking. The orientation of the elements was approximately as follows: 40% longitudinal, 28% transverse, 20% irregular and 12% pegs. The northern half of the cutting was fairly similar in construction to that exposed in Cutting 1. Most of the elements here were transversely laid. The large proportion of longitudinal elements was predominantly evident in the southern half of the cutting. These elements were also relatively larger than those on the northern side of the cutting, ranging in diameter from 20mm to 98mm, the average diameter being c. 40mm. There were also some planks present that were not previously noted in any of the other cuttings. The pegs holding the superstructure in place were noted through the central part of the togher as well as along the sides. Some of the pegs protruded above the surface of the site by 50–200mm, which would have made walking along it difficult. The construction of the substructure reflected the material from the superstructure.

An interesting detail noted during this excavation was the subtle change in the construction of the site at certain locations. These changes may represent a direct response to local environmental conditions. This is particularly noticeable at the southern extent of Cutting 3, where there was less wood present. From preliminary examinations of the peat, this dispersal of wood appears to have occurred because of extremely wet localised ground conditions. The leather shoe was also located in the wettest part of the cutting. The southern half of Cutting 1 contained some larger, more irregularly placed elements that may represent a repair to the togher at that particular location. This is also possible in relation to the larger, longitudinal elements in the southern part of Cutting 4. The most consistent construction pattern in all four of the excavated cuttings was displayed in Cutting 1.

The site was initially traced for a length of 180m in 1998. This was extended to approximately 230m during this season’s work, when it was identified in the last four drain faces at the southern side of the bog. As mentioned above, there is a substantial amount of bog extending further southwards that has not been disturbed by drainage ditches as it remains in private ownership. As a result, the true southern extent of the site has not been located.

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