The structure, a togher, which is the Irish term for a wooden trackway laid across boggy or waterlogged ground, was uncovered during Bord na Móna peat-cutting operations in the Blackwater works in 1983. It runs SSE to NNW, crossing between Bloomhill townland in County Offaly and Ballynahownwood in County Westmeath, and it is built with a quiet, methodical ingenuity: parallel birch roundwoods between about seven and thirteen centimetres in diameter, with brushwood and twigs packed between them, and a single roundwood set at an oblique angle underneath as a substructural support. Several of the timbers still carry visible toolmarks, small but direct evidence of the hands that shaped them.

When Halpin first described the site in 1984, he identified both a timber trackway and a stone roadway component and assigned the whole to the medieval period. Subsequent excavation by Breen in 1987 added considerably more detail. The stone flagstone surface, he found, rested on a peat foundation with a layer of brushwood beneath it, and the finds retrieved from the site pointed firmly toward the thirteenth century: horseshoes of that period's type, along with two fragments of leather shoe, recovered from above the stone roadway. A piece of stone resembling the flags of a nearby related site also rested on one of the roundwoods, suggesting the two structures were once part of the same crossing. Local folklore, recorded by Breen, Parkes, and Bradshaw in 1988, associates the trackway with a pilgrimage route connecting the great monastery of Clonmacnoise, a few kilometres to the south in County Offaly, with the old churchyard at Killomenaghan in County Westmeath. Whether or not that tradition preserves an accurate memory, the physical evidence of worn horseshoes and discarded shoe leather does conjure the image of travellers, on horseback and on foot, picking their way across the bog along this improbable road.