Tochars, as they are sometimes spelled, were constructed from timber, brushwood, peat, or a combination of materials laid down across the wet and yielding surface of a bog. They are among the more quietly remarkable survivals in the Irish archaeological record, preserved precisely because the waterlogged, oxygen-poor conditions that made crossing a bog so difficult in the first place also prevented the organic materials from decaying.

This particular example is classed as a class 3 togher, a designation that refers to its method of construction rather than its age or significance. It was noted during a field survey carried out in 1988, with details communicated by B. Raftery, a scholar closely associated with Irish wetland archaeology. The work formed part of a broader effort by the Irish Archaeological Wetland Unit, based at University College Dublin, to systematically record the bogland trackways of the Irish midlands before drainage, turf-cutting, and development could erase them entirely. Many such tochars date from the Bronze Age or Iron Age, though without excavation or dating analysis it is not possible to assign a specific period to the Derryad example on the basis of the survey alone.