Unremarkable at a glance, their upper surfaces carry a dense, carefully worked programme of prehistoric carving whose full meaning has never been decoded. The more elaborately decorated of the two blocks bears cup-and-ring marks, the most common form of Atlantic rock art, in which a shallow circular depression, the cup, is surrounded by one or more incised concentric rings. Here the largest such motif spans nearly half a metre across, an unusually generous scale. Alongside it are smaller cup-and-ring combinations, isolated cupmarks, straight grooves, one of which ends in a cupmark, and a dense patch of pocking enclosed within a ring. A loose slab at the base of the rock adds a further decorated surface, its cup-and-two-ring motif sitting beside natural depressions whose outlines have been deliberately enhanced by pocking, blurring the boundary between what the stone offered and what a prehistoric hand chose to emphasise.

The second site, a few dozen metres to the north-west, is a large sandstone boulder sitting at around 147 metres above sea level on a south-east-facing slope overlooking the Owroe and Inny river valleys. It measures roughly 3.5 metres by 4.2 metres, rising to 2.1 metres at its south-west end, and its decorated surface occupies the flatter north-eastern half. The motifs here are heavily weathered, with clear evidence of freeze-thaw action over centuries; part of one outer ring is simply missing, almost certainly lost to repeated cycles of frost damage. The carved surface includes multiple cup-and-ring and cup-and-two-ring motifs, a long curving groove of pickmarks running between two of the larger compositions, a series of nine cupmarks with intersecting meandering grooves, and a curvilinear line that terminates abruptly at a natural ledge in the rock. The precision of the recorded measurements, compiled by Alison McQueen and Vera Rahilly and drawing on earlier survey work by A. O'Sullivan and J. Sheehan published by Cork University Press in 1996, gives some sense of how painstaking this carving was, individual ring widths measured in millimetres, depths rarely exceeding a centimetre.

The age of Irish rock art is broadly attributed to the Neolithic and Bronze Age periods, though precise dating remains difficult. What is clear at Tuar An Chladáin is that someone, or more likely several people across perhaps a long span of time, chose these particular stones on this particular slope for sustained, deliberate marking. The stream running about thirty metres to the north-west and the open prospect down towards the river valleys below may both have been part of whatever logic governed that choice.