Roughly D-shaped, measuring about 11.5 metres north to south and less than a metre in height, it sits atop a low natural rise and is bordered along its eastern edge by a field fence. It appears on no Ordnance Survey maps from either 1838 or 1922, which is itself quietly telling. The disturbance along its north-western edge has exposed the interior: a concentration of small to medium-sized stones, the kind of construction typical of a cairn, a burial or marking mound built from gathered stone rather than cut or quarried material. Two hollows in the surface suggest areas where the ground has subsided and been filled in over time, and some irregular dumps of earth and stone on the south-western edge look to be relatively recent additions, the casual result of agricultural tidying rather than any deliberate intervention.

What makes this mound particularly interesting is what local tradition says lies beneath it. According to information gathered from people in the area, the cairn overlies a souterrain, an artificially constructed underground passage or chamber, typically associated with early medieval settlement in Ireland and often used for storage or refuge. If that account is accurate, the visible cairn may represent only the surface layer of a more complex site. Adding further weight to this corner of the landscape, a rath sits just 140 metres to the east. A rath is a roughly circular earthwork enclosure, usually the remains of an early medieval farmstead, and their presence alongside souterrains is well established in the Irish archaeological record. The clustering of these features in a small area of coastal Co. Mayo suggests a settlement history that has left only faint traces above ground, easy to pass without a second glance.