It is a modest object by any measure, just 34 centimetres tall with an arm span of 47 centimetres, and its surface carries no carving, no inscription, no ornament of any kind. That plainness is not incidental. It speaks directly to the circumstances under which it was used.

During the Penal Laws, the period broadly spanning the late seventeenth and eighteenth centuries when Catholic worship was severely restricted in Ireland, congregations gathered at outdoor sites known as Mass rocks to hear clandestine services. The stone altar at Carragh was one such site, recorded as a place where Masses were offered in penal times by local historian Glynn in 1908. The cross set into its centre would have served as the focal point for those gatherings, conducted outdoors and out of sight of authorities, in conditions that made any elaborate religious furnishing both impractical and dangerous. A rough-cut cross on a field altar was sufficient, and that sufficiency is still visible in the object today.

What makes the site quietly remarkable is that it does not appear to have slipped entirely into the past. The monument is regarded as a place of worship still, suggesting a continuity of reverence that has outlasted the legal pressures that first made this kind of open-air observance necessary.