Yet this particular slab, lying a few metres to the north-east of the structure known as the Priest's House, carries a quietly significant mark: a single incised Latin cross, its four arms cut in one continuous line and each terminal gently expanded into a wider point. It is an understated object, and that restraint is itself characteristic of early Irish Christian stonework.

The slab was catalogued by Patrick Healy in a 1972 Office of Public Works survey of ancient monuments at Glendalough, where it appears as number 170 in his supplementary list. Healy described it as a small rectangular piece of mica schist, a fine-grained metamorphic rock common in the Wicklow uplands, measuring something over a metre in length, roughly 0.4 metres wide, and only about 0.06 metres thick. Cross-slabs of this kind, essentially grave-markers or devotional stones incised with a simple cross rather than sculpted in relief, are found across early Christian sites throughout Ireland and represent one of the most modest and widespread forms of early medieval religious expression. The expanded terminals on the cross arms are a detail worth noting; they appear frequently on Irish cross-slabs and are thought to reflect an awareness of more elaborate metalwork and manuscript cross forms, translated here into the plainest possible medium. The slab sits 3.20 metres to the north-east of the Priest's House, a small Romanesque structure within the broader Glendalough complex whose precise original function remains a matter of scholarly discussion.