Not timber planks or hewn beams, but bundled hazel brushwood pressed into the soft ground, layer upon layer, until a surface emerged that could carry a person, an animal, or a load across terrain that would otherwise swallow them whole. One such structure survives at Corlea, a class 3 togher, which is the Irish term for a bog road or trackway, running roughly northeast to southwest through the peat. It measures 2.3 metres wide and sits roughly 35 centimetres deep, a modest but deliberate piece of engineering laid down in a landscape where the ground itself could not be trusted.

Corlea is already known to archaeologists as the site of one of the most remarkable Iron Age roadways in Europe, but the bog here preserves more than one layer of human activity. This particular togher is a class 3 construction, meaning it relies on brushwood rather than the large oak planks associated with the more celebrated Iron Age trackway nearby. Hazel was a practical choice, flexible, widely available, and quick to coppice, and its dense bundling would have distributed weight across the unstable surface of the bog. The presence of some small roundwoods alongside the brushwood suggests a degree of structural reinforcement, though the overall impression is of a working, functional path rather than a monumental undertaking. The bogland preserved it where open air would long ago have rotted it away.