2002:1584 - TOGHER AND BARRYSBROOK, Offaly

This licence covered the excavation of a series of wooden structures constructed within a palaeo-channel and a wooden platform at the end of the palaeo-channel (No. 1583, Excavations 2002, 02E0932). The wooden structures varied in complexity and size and were found over a length of 350m.

The wood was not continuous along the 350m length of the palaeo-channel. Generally, the sites excavated at the southern end of the palaeo-channel were small, loosely scattered arrangements of wood, and those at the northern end were of trackway type. The sites at the southern end of the channel averaged 1.2m wide, 2m long and 0.4m deep. They were generally composed of around twenty brushwoods, with occasional roundwoods, arranged in a non-structured fashion. Some of the wood associated with these small, discrete sites had worked ends, suggesting that the sites performed a function and were not naturally occurring. The sites most likely represent small foot holdings of wooden branches laid down in the palaeo-channel as a safe crossing-point.

The palaeo-channel was composed of three layers of peat at most locations investigated. The upper layer was yellow Sphagnum cuspidateum peats, which probably represented the flowing water; the middle layer was more humified, orange/brown Sphagnum peats; and the bottom layer was dark brown peat with many organics, such as twigs and leaves.

The trackway excavated along the northern length of the palaeo-channel averaged 2.5m wide and 0.3m deep and could be traced, albeit with some significant gaps, for a distance of 250m. The togher was composed of several roundwoods laid longitudinally across the site, with brushwood and twigs interspersed between the roundwoods to form quite a robust construction. The roundwoods averaged 1.2m long and 0.1m in diameter. The brushwood had similar lengths but averaged 0.02m in diameter. This togher, which ran along the northern end of the palaeo-channel, joined up with the platform.

This large multi-layered platform represents the known terminal of the palaeo-channel and was in the central area of the bog, c. 200m from the nearest dry land. The platform was constructed near a large Sphagnum pool. The wooden platform was exposed on the field surface and was in moderate to poor condition. The wood was dry and brittle owing to prolonged exposure and repeated milling. Roundwood elements accounted for c. 25% of the exposed structure. The remaining 75% comprised brushwood. The roundwoods clearly functioned as structural stabilisers, but their positions within the platform do not point to a highly organised or carefully planned construction. It may be suggested that any available wood was used in the construction of this platform, given that untrimmed tree branches formed part of the structural elements. It appears that this site may have been constructed using layers of very similar wood, and no definite super- or substructure was noted. The platform measured 13m by 10m and had a maximum depth of 0.4m. Preliminary analysis of the wood indicates that the majority was Pinus sylvestris (Scots pine) and Betula sp. (birch).

Only two finds/artefacts were retrieved during the excavations along the length of the channel and at the wooden platform, and therefore it is difficult to conclude why these sites were constructed and what type of activities were carried out on the platform. The two artefacts were a large blackthorn rod, 1.21m long and 0.05m in maximum diameter, slightly pointed at one end and rounded at the other, and an octagonal wooden artefact, 1.2m long and 0.18m in diameter. The function of these artefacts is as yet unknown.

Two sites along the line of the palaeo-channel have been dated at University College Dublin by the Irish Archaeological Wetland Unit to 1365–919 BC and 1108–800 BC, and the platform at the end of the channel was dated to 2282–1952 BC. These dates suggest that the platform was not in use at the time that the sites were constructed along the line of the palaeo-channel. The palaeo-channel may have been crossed only at the southern end of the channel, and at the northern end it appears to have been used as a natural route. The channel would have been a natural route across a peat bog that would have been a large expanse of treacherous Sphagnum pools and overgrown grasses, and the platform may have been used as a hide or hunting platform to provide access to animals and plants that were not readily available on the dryland fringes.

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