One of them has since left the hillside entirely; the other remains where it was found, propped against a field fence at around 149 metres above sea level. The separation of a pair of stones that once shared the same patch of ground gives this site an odd, incomplete quality, as though half a conversation has been moved to a different room.

Rock art of this kind, which typically dates to the Bronze Age, consists of cup-marks and ring motifs pecked into stone surfaces, the meaning of which remains genuinely unclear. The smaller of the two Knocknakilton stones, measuring roughly 1.2 metres by 0.8 metres, was at some point incorporated into a field fence before being removed and taken into the care of Oidhreacht Chorca Dhuibhne, the heritage organisation for the Dingle Peninsula. Its surface carries a notably elaborate design: a large cup-mark surrounded by three concentric circles, with a radial line cutting outward from the central cup through a gap in the inner circle and across the outer rings. A second, diametrically opposing radial line is formed not by deliberate carving but by a natural fissure in the stone, which either coincidentally mirrors the carved line or was perhaps chosen for exactly that reason. At least six further cup-marks and a partial cup-and-circle are also present, though some detail has been lost to spalling and erosion.

The larger slab, still in situ against the field fence, is a more worn and ambiguous object. Measuring 2.25 metres in length, its surface is sufficiently weathered that some depressions may be natural rather than carved. Archaeologist Finlay recorded a cup-mark at its edge in 1973; a subsequent spall has since broken away, taking that mark with it. What remains includes at least ten definite cup-marks and two cup-and-circles, one of them with a radial line. J. Cuppage documented both stones in the 1986 Dingle Peninsula archaeological survey, and that record remains the principal source for understanding what was once a pair.