A souterrain is an underground stone-lined passage or chamber, typically built during the early medieval period and associated with settlement sites; they were used variously for storage, refuge, or ventilation. This one was recorded as lying within a cashel, a type of stone-walled enclosure that usually surrounded an early medieval farmstead or settlement. By the time anyone went looking for it in earnest, it had effectively ceased to exist as a visible feature.

Two nineteenth-century antiquarians documented the site independently. W. G. Wood-Martin noted it in 1887 to 1888, and Fox Milligan followed with his own account in 1890 to 1891. Both placed the souterrain within the cashel enclosure, and their records gave the site enough credibility to earn it a place in later monument inventories. But when fieldwork was carried out in 1994, the cashel itself had become so heavily colonised by scrub vegetation that neither the enclosure walls nor any trace of the souterrain could be identified on the ground. The monument had not necessarily been destroyed; it had simply been swallowed.

This is a fairly common fate for low-lying earthwork and stonework sites across Ireland, where a generation or two of unchecked vegetation can render a recorded monument effectively invisible. What lingers here is the gap between the confident nineteenth-century descriptions and the blank field note from 1994, a reminder that the documentary record and the physical landscape do not always agree, and that absence of evidence is not quite the same as evidence of absence.