The one at the centre of that line, tucked into a thicket of blackthorn and hazel in a pasture field at Collagh, is now largely swallowed by scrub, brambles, and ferns, which means its careful construction is easy to miss. A ring barrow is a roughly circular earthen burial monument, typically consisting of a raised central platform enclosed by a ditch or fosse, and this example follows that form precisely, though on an intimate scale.

The monument sits on the narrow crown of a northwest to southeast ridge in gently undulating terrain. The central platform measures five metres in diameter, defined by a low scarp sixty centimetres high and a slight internal lip around a metre wide. Outside that, a shallow fosse, roughly 1.7 metres across, encircles the whole, and the natural fall of the ground toward the southwest gives extra visual emphasis to the earthworks on that side, where they are also best preserved. The fosse is shallowest to the north and west, but the overall form remains legible. What is striking is that two companion barrows sit within just a few metres, one immediately to the northwest and another only five metres to the southeast, the three forming a tight procession along the ridgeline. None of them appeared on the Ordnance Survey six-inch maps of 1838 or 1931, suggesting they were either unrecognised or already obscured by that point. The ground falls away roughly a hundred metres to the south and southwest toward the Trimoge River, which bends just to the northwest of the ridge, and though the surrounding ridges largely close off any broader prospect, there is one gap to the northwest through which Nephin Mountain and the Nephin Beg Range come into distant view.