At Glasha Beg, a later drystone field wall, standing about 1.5 metres high, follows the exact line of a much earlier structure beneath it, and a spread of collapsed stone material visible under the northern stretch suggests the boundary-makers were not building from scratch so much as cannibalising what was already there. The structure in question is a cashel, the Irish term for a stone-built ringfort, a roughly circular enclosure defined by a substantial stone wall rather than an earthen bank. This one went unrecognised as a definite site until aerial photography prompted its inclusion in the Record of Monuments and Places in 1996.

The cashel is large, measuring roughly 52 metres across on its northeast to southwest axis and about 45 metres on the northwest to southeast, making it a substantial example of its type. What survives away from the modern boundary wall is a wide bank of collapsed and grass-covered stone, between three and a half metres across, with the outer face still rising to about 1.6 metres in places. Intermittent wall-facing, where the original dressed stonework is still legible, shows most clearly at the southeast. Inside, the ground slopes gently down toward the southwest, and a separate grassed-over wall, about 45 metres long, meanders across the interior from roughly northwest to southeast before continuing beyond the cashel's edge. Its purpose is not recorded. What makes the wider landscape here particularly striking is the density of related monuments: two other cashels sit within 31 metres to the north and west, an enclosure lies about 71 metres to the northeast, and a fourth cashel is visible roughly 108 metres to the southeast. The whole area sits within a large multiperiod field system set among undulating pasture and the bare limestone pavement characteristic of this part of Clare, suggesting generations of occupation and land management layered over one another across the same ground.