Somewhere beneath the cutaway bog north of Lullymore in County Kildare, the remains of a carefully engineered early medieval road lie buried in the peat. A togher is a timber trackway laid across boggy or waterlogged ground, and this one is among three that converge on Derrybrennan townland, a small island of elevated ground rising out of a wide expanse of bog. What makes this particular example quietly remarkable is the precision of its construction: long oak planks, averaging around 4.5 metres in length, laid in parallel pairs along a roughly north-north-west to south-south-east axis, each end morticed and pinned into the peat with axe-sharpened oak pegs roughly 60 centimetres long. Transverse oak roundwood sleepers supported the planks beneath. The whole structure was, in effect, a prefabricated wooden road, engineered to carry movement across ground that would otherwise have made passage impossible.

The togher came to light after Bord na Móna, the state peat-harvesting company, reported its discovery during bog-cutting operations. Excavation followed in 1964 to 1965, carried out by Rynne on behalf of the National Museum of Ireland. Rynne traced the southern limits of the trackway, followed its course northward for roughly half its estimated total length of about 1,500 metres, and excavated a section nine metres long and one metre wide, with additional minor cuttings at other points. The togher was found at a depth of around 1.2 to 1.5 metres below what had been the original surface of the bog, most of which had by then been cut away. Radiocarbon dating subsequently placed it at 1200 plus or minus 20 BP, which places its construction in roughly the eighth or ninth century. The route it served connected higher ground in Ticknevin townland to the north with the Derrybrennan island of firm ground to the south, suggesting that this small elevated patch was a destination worth reaching, perhaps for settlement, farming, or ritual reasons that the bog itself has not yet given up.