There is no earthwork to catch the eye, no hollow in the ground, no tell-tale scatter of stone. The field at Kilpatrick looks exactly like every other field around it, which is precisely what makes the presence of a known underground structure here so quietly disorienting.

A souterrain is a man-made underground passage or chamber, typically constructed during the early medieval period in Ireland using dry-stone walling and large roofing slabs. They are found across the country in considerable numbers and are generally thought to have served as places of refuge or cool storage, often associated with nearby settlements or ecclesiastical sites. The Kilpatrick example sits approximately forty metres south-south-west of a children's burial ground, a type of site known in Irish tradition as a cillín, where unbaptised infants and others excluded from consecrated ground were interred, often in locations with much earlier sacred or ritual associations. The proximity of the souterrain to that burial ground may be coincidental, or it may reflect a longer continuity of use in this part of the landscape, though the ground itself gives nothing away.