To most drivers, this is simply the way the road goes. To those who study early medieval settlement patterns, it is a potential fingerprint of a vanished world.

An ecclesiastical enclosure, in early Christian Ireland, was typically a roughly circular or oval boundary, often a bank and ditch, that demarcated sacred ground around a church or monastic settlement. These enclosures were a defining feature of the Irish church from roughly the fifth century onwards, and although the physical boundaries themselves frequently disappeared over the centuries, their outline often survived in subtler ways, absorbed into the surrounding landscape as field boundaries, property lines, or the gentle curves of rural roads. At Clonlost, the curvilinear shape of the roadway to the north, east, and south-east has been interpreted as possibly tracing just such an enclosure, a suggestion made by Leo Swan in 1988. Swan was a pioneering researcher in the aerial and cartographic study of early ecclesiastical sites across Ireland, and his work drew attention to how much could be read from the shapes roads and fields had quietly preserved. At the centre of this possible enclosure stand the ruins of a medieval church, itself surrounded by a graveyard containing post-medieval memorials, suggesting that this place has held a religious function across many centuries, even as the earlier structures faded and were replaced.