The boulder, roughly a metre high and just over a metre in its longest dimension, was known locally as the Cailleach, meaning the Hag. In Irish folk tradition the Cailleach is an ancient, elemental female figure, associated with the land, weather, and a kind of austere protection. That association shaped a very particular burial practice: families who had lost a baby before baptism, and who therefore could not inter the child in consecrated ground under Catholic Church rules, brought them here instead, to rest under the guardianship of the stone.

The site sits in what is now plantation forestry, on marginal ground shaped by the bog that still defines this corner of Mayo. To the south-west, the Nephin Beg Mountains mark the far horizon. Immediately to the west of the boulder, a spring runs through a two-metre strip of damp ground. The spring was not considered a holy well in the formal sense, yet local tradition held it to have a sacred or special quality, a distinction that mattered in a landscape where the boundary between the ordinary and the numinous was drawn carefully. A low earthen bank borders the western side of the spring, curving slightly over a length of about eight metres. To the east of the boulder there is a slight rise in the ground, three to four metres across, though a pine tree growing at its edge suggests this may simply be a natural build-up of peat around the roots rather than a burial mound. There are no visible grave markings at surface level.

Places like this, known in Irish as cillíní, were used across the country for centuries to inter those excluded from churchyard burial: unbaptised infants, stillborn children, and occasionally others on the margins of official religious life. They were typically located at liminal spots, old boundaries, water sources, ancient stones, places that already carried some sense of being set apart. The Crocknacally site fits that pattern precisely, gathering together a glacial boulder with its own named identity, a spring with perceived sacred properties, and an earthen boundary, all tucked into rough ground that the surrounding community clearly understood as somewhere between the ordinary world and something older.