It is not a rough track worn by repeated footfall, but a deliberately engineered surface, just over a metre and a half wide, laid with cobbles and small flagstones and reinforced in softer patches with deposits of brushwood. The care that went into its construction suggests it was not accidental or provisional. Someone, or a community of someones, needed this route to hold.

The track has been dated to between 1450 and 1030 BC, placing it firmly in the Bronze Age, a period when Ireland's boglands were far more actively crossed and managed than their current emptiness might suggest. Bog roads of this kind, sometimes called toghers, were a practical response to the challenge of moving people, animals, or goods across ground that would otherwise swallow a traveller. The Derryfadda example is notable for its combination of materials: the cobbled and flagged sections gave a firm footing on more stable ground, while the brushwood acted as a raft of sorts where the peat grew wetter and less reliable underfoot. The overall width of 1.42 metres is enough for a single person with a loaded animal, or perhaps two people passing carefully in opposite directions.