A cashel is a roughly circular or subrectangular stone enclosure, typically of early medieval date, built from dry-laid limestone without mortar. This one sits on a low rise of the characteristic bare pavement, within a large multiperiod field system, and has appeared on Ordnance Survey maps since 1842 under the name 'Cahernaspeekee'. When Tim Westropp, the indefatigable Clare antiquarian, was gathering local knowledge in 1915, one of his informants questioned whether that name was even genuine. The Irish form 'Cathair na Spící', recorded on Tim Robinson's 1977 map of the Burren, translates roughly as 'the fort of the spikes' or 'the spiked enclosure', and it is not entirely clear what that refers to, or whether the name has any real antiquity at all.

Westropp visited the site twice, in 1895 and again in 1915, and those two visits together tell a story of quiet, incremental destruction. The cashel is subrectangular, measuring just over thirty-two metres east to west and nearly thirty-two metres north to south, with a double-faced stone wall built from large, horizontally laid limestone slabs up to one and a half metres long. When Westropp first inspected it, the wall still stood to 1.85 metres in height, the entrance jambs at the south were intact, and the structure retained what he described as a terrace within the wall thickness, with upright slabs set against the inner face 'like a veneer'. He noted the masonry as good but open-jointed, and thought the style suggested a later construction date than some of the grander cashels nearby. By his return visit in 1915, the entrance jambs had gone, the wall terrace had been damaged, and there was digging visible in the interior. A lintel stone of 1.35 metres, still in place in 1915, had disappeared by the time of a further inspection in 1997. The wall has since slumped to a spread of rubble eight to nine metres wide in places, burying both inner and outer faces. A later drystone field wall has been built directly over the outer face, a pragmatic reuse of ready-cut stone that was probably not unusual across the Burren.

The cashel does not sit in isolation. Within a hundred metres there is a second cashel to the south-southeast, a hut site to the south, and an enclosure to the northeast, all part of that larger field system that clearly saw sustained activity across multiple periods. The NW quadrant of the interior is noticeably lower than the rest of the floor, by about thirty centimetres, most likely the result of the same undocumented digging that stripped the entrance and damaged the wall terrace sometime between Westropp's two visits.