Among its quietly noted features is an old field boundary, the kind of structure that most walkers pass without a second glance, yet which in this landscape carries considerable age and context. Field boundaries of this type, whether built from stacked stone, earthen banks, or some combination of both, represent some of the most persistent evidence of human land use in rural Ireland, often surviving for centuries precisely because no one found it worth the effort to remove them.

The boundary at Coomasaharn is catalogued in O'Sullivan and Sheehan's archaeological inventory of south-west Kerry, published in 1996, which systematically documented monuments across one of Ireland's more archaeologically dense regions. Kerry's upland and coastal zones contain layer upon layer of human activity, from early prehistoric clearance and farming through to post-medieval landholding patterns, and field boundaries frequently blur the lines between these periods. Without closer survey or excavation, the precise date of any individual boundary is difficult to pin down, which is part of what makes even modest examples worth noting. They are, in a sense, the connective tissue of a farmed landscape, less dramatic than a ringfort or a souterrain but no less telling about how people organised their lives around land.