In fact, it is a rath, the Irish term for a ringfort, the type of enclosed farmstead that was built and occupied across Ireland from roughly the early medieval period. Thousands survive in various states across the country, but what makes each one worth attention is the particular way time has treated it, and at Tullerboy, that story is written in layers that reward patience.

The site sits in pasture, approximately 96 metres west of the townland boundary with Drombeg, and it was already being mapped with some care by the late nineteenth century. The 1897 edition of the Ordnance Survey Ireland 25-inch map records it as a sub-circular enclosure measuring roughly 39 metres north to south and 36 metres east to west, defined by a scarp, which is essentially an earthen slope or bank, and an external fosse, meaning a surrounding ditch. At some point after 1700, a field boundary was pushed through the southwestern section of the monument on a northwest to southeast alignment, cutting across the older earthwork and leaving a permanent mark on its outline. That post-medieval intrusion is still detectable today and gives the site its slightly interrupted character.

Orthophotographs taken between 2005 and 2012 for the Ordnance Survey Ireland showed the monument clearly: a circular area enclosed by a tree-covered bank, with an overgrown fosse still traceable from the north, east, south, and southwest. A Google Earth image dated 14 September 2019 confirmed it remains visible from above, with cropmarks, the ghostly outlines that buried or levelled features leave on growing vegetation in dry conditions, revealing the course of the flattened fosse on the southwestern to northwestern arc. On the ground, the trees that have colonised the bank are likely the most immediate clue to its presence, since ringforts across Ireland tend to accumulate scrubby growth that farmers historically left undisturbed out of a mixture of practicality and folklore. The overgrown fosse, where it survives, may be discernible as a slight hollow running around the outer edge of the bank. The field boundary cutting through the southwest is worth looking for as a reminder that these monuments were not always treated as ancient curiosities but simply as inconvenient irregularities in otherwise useful land.