The ground shows no earthworks, no banks, no ditches. What survives instead is a ghostly ring of pale vegetation, roughly nineteen metres across, with faint traces of old cultivation ridges running north to south across its interior, and a small depression slightly west of centre that hints at something buried beneath. It is the kind of site that rewards patient looking and rewards it differently depending on what you believe you are seeing.

The 1837 Ordnance Survey Fair Plan recorded the feature as a circular enclosure and labelled it simply "fort", which is how it entered the archaeological record. A ringfort, in early medieval Ireland, was typically a farmstead enclosed by one or more earthen banks and ditches, the defended homestead of a farming family. Thousands survive across the country. But the Mountmurray example sits on demesne land belonging to Mount Murray house, which lies some 375 metres to the north-north-west, and this proximity raises a complicating possibility. The earthwork may have been pressed into service as a landscape feature within the designed grounds of the estate, or it may have originated as a tree-ring, a planted circular grove of ornamental trees, constructed sometime after 1700. The L-shaped vegetation growth and the slight depression at the centre do suggest the possible presence of a souterrain, an underground stone-lined passage often associated with genuine early medieval ringforts, but the evidence stops well short of confirmation. Lough Owel lies 140 metres to the east, visible from the hilltop, and it is tempting to imagine the spot chosen for its prospect, whether by an early medieval farmer or an eighteenth-century landscape designer.