Around 4.2 metres long and less than half a metre deep, the depression looks at first like nothing more than an old furrow or a quirk of the ground. But it is most likely the surface trace of a collapsed souterrain, an underground passage or chamber built during the early medieval period, typically constructed from dry-stone walling and roofed with large lintels. When those lintels finally give way, the ground above settles into exactly this kind of long, narrow hollow.

The ringfort in which it sits, a roughly circular enclosure of the kind that dots the Irish countryside in the thousands, occupies a natural rise in gently undulating grassland, with open views in every direction. That elevated position was almost certainly deliberate. Early medieval farming families who built and lived within ringforts chose sites that offered both visibility and drainage, and the high ground at Littletown delivers both. A second ringfort sits around 190 metres to the south-west, suggesting this was once a settled, organised landscape rather than isolated occupation. Souterrains associated with ringforts are thought to have served various purposes, most probably food storage, given the cool and stable underground temperatures, though they may also have offered a place of concealment in times of danger. The one at Littletown, if that is indeed what the depression represents, has long since lost its roof and any direct access, leaving only the outline of what was once a deliberate and carefully made underground space.