It is not displayed, not signposted, and not precisely located. It simply sits within the cashel, the dry-stone enclosure wall that once defined the boundaries of the early Christian monastic community on High Island, doing the quiet structural work of an ordinary building stone while carrying on its face a composition of considerable care and skill.

The slab bears a roughly equal-armed cross rendered in three incised lines, its four arms terminating in D-shaped ends. The left and right terminals are decorated with key patterns, those interlocking geometric designs that appear across early medieval Irish and Insular stonework, though the detail on the top and bottom terminals is less clear from the available record. At the centre of the cross sits a roundel, itself containing a cruciform form with a small boss at its middle, a boss being a rounded raised knob often used as a focal point in early medieval decorative carving. There are also faint indications of a smaller roundel in the upper left quarter of the cross. The description, compiled by researcher J. Higgins in 1987, was made from a photograph rather than direct examination of the stone, which accounts for some of the uncertainty around the finer details.

High Island, known in Irish as Ard Oileán, lies several kilometres off the Connemara coast and is accessible only by arrangement, typically in calm weather. The monastic site itself is substantial for so small and exposed a place, and the cashel wall into which the cross-slab has been incorporated is a significant surviving feature of the enclosure. Visitors who make it to the island should be aware that the slab has no fixed marked position within the wall, meaning it requires a slow and attentive look rather than a direct approach.