This is a cashel, a type of ringfort defined by a stone rather than an earthen boundary wall, and the one at Caheraphuca has been worn by centuries into something more like a rumour of a wall than a standing structure. The name itself is suggestive: "caher" derives from the Irish cathair, meaning a stone fort, while "phuca" points to the púca, a shapeshifting spirit of Irish folklore. Whether the name came before the reputation or the other way around is now impossible to say.

The enclosure measures roughly 30 metres north to south and 26 metres east to west internally, which would have made it a reasonably substantial settlement in its day. The boundary wall has survived unevenly: along the north-northwest to east arc, the original outer face still stands to about 0.8 metres, while elsewhere the structure has collapsed into a broad stone spread. That spread reaches its greatest width at the southeast, where it fans out to 8 metres across. A later stone wall was built along the inner edge of this spread, running north-northwest to south-southeast, suggesting the site saw some reuse or modification after its original construction. The interior slopes gently downward toward the south, and within it sits an oval-shaped house platform, measuring 16 metres east to west and 8 metres north to south, still legible as a distinct feature on the ground. Ringforts of this kind are generally associated with early medieval settlement in Ireland, roughly the period between the sixth and tenth centuries, functioning as enclosed farmsteads for a single family or small community.