This is a cashel, the Irish variant of the ringfort, built not from earthen banks but from stone, which was in ready supply across the limestone-rich Burren landscape. What gives this particular example a quiet intrigue is what lies inside: scattered spreads and piles of stones that archaeologists suspect may be concealing earlier features beneath them, structures or deposits that have never been properly investigated.

The cashel measures roughly 19 metres north to south and 22 metres east to west, making it a moderately sized example of the type. Its wall, nearly two metres wide, retains facing stones on both its inner and outer surfaces, with surviving heights ranging from just a few centimetres to nearly two metres depending on the section. A gap of two metres on the western side is almost certainly the original entrance, a detail that aligns with patterns seen across many Irish cashels, where entrances were typically positioned to face away from prevailing Atlantic weather. The site appeared on the 1916 edition of the Ordnance Survey six-inch map, though it was listed only as an "Enclosure" in the Record of Monuments and Places compiled in 1996, a designation that understates what is clearly a well-defined and substantially intact structure. Approximately 70 metres to the north sits a larger cashel, suggesting this part of Gragan was once a more densely settled landscape than it might appear today, with adjacent enclosures perhaps functioning in relation to one another, one possibly serving an ancillary role to the other.

The site occupies ground that opens up with views stretching from east to south-southwest, a positioning that would have made practical sense for any early medieval community keeping watch over land and livestock. The stone piles in the interior remain unexcavated, and what they conceal, whether collapsed structures, pits, or simply field clearance, is still an open question.