At Tullahennel in north County Kerry, the Ordnance Survey recorded a circular enclosure on both its nineteenth-century editions, marking out what was almost certainly a rath, the Irish term for a ringfort, one of the thousands of roughly circular earthwork enclosures built across Ireland during the early medieval period, typically between the fifth and twelfth centuries, and used as farmsteads by families of varying social rank. No surface trace of it survives today.

The site sits immediately to the north-east of another recorded monument in the same townland, suggesting this was once a landscape with some density of early settlement. C. Toal's North Kerry Archaeological Survey, published in 1995 through Brandon in association with FÁS, catalogued the enclosure as entry number 316, drawing on the cartographic evidence that the Ordnance Survey had preserved even as the physical remains disappeared. That the maps caught it at all is largely a matter of timing: the first Ordnance Survey of Ireland in the nineteenth century recorded earthworks that were, in many cases, already under pressure from agricultural improvement, and by the time the second edition was produced, some had already begun to fade. Here, whatever earthen banks or ditches once defined the enclosure have been levelled entirely, absorbed back into the surrounding farmland.