A roughly cubic sandstone boulder, about a metre in each direction, sits quietly on the west side of a road bank in Knocknacreha, County Waterford. It looks, to a passing eye, like nothing more than a large fieldstone. Its Irish name tells a different story. The stone is correctly known as Cloch na gCeann, meaning the Stone of the Heads, and the tradition attached to it holds that the severed heads of executed criminals were once displayed upon it.

The name was partially garbled by the time cartographers recorded it. The 1926 edition of the Ordnance Survey six-inch map rendered it as Clogh na gCrann, a transcription that obscures the original meaning. Before it was moved, the stone stood on the east side of the road, towards the top of a south-facing slope, a position that would have given any display upon it considerable visibility to those passing below. It now rests approximately thirty metres from that original location, shifted to the west side of the road bank at some point after the map was made. The practice of displaying heads after execution was not uncommon in early modern Ireland and medieval Europe more broadly, serving as a public assertion of judicial authority. A stone associated with such a function suggests this was once a site of some local legal or territorial significance, though the precise history behind the tradition at Knocknacreha is not recorded.