Megalithic tomb, Cornagillagh, Co. Leitrim

That is not a riddle; it is simply the current condition of a site that was once substantial enough to have a name. Local people called it the Giant's Grave, the kind of folk designation that tends to attach itself to large, ancient stonework across Ireland, a shorthand for something old and not fully understood.

When archaeologists Ruaidhrí de Valera and Seán Ó Nualláin examined the site for their 1972 Survey of the Megalithic Tombs of Ireland, they found four upright stones among an amorphous scatter of others, some of which may have been deposited by farmers clearing adjacent fields rather than by Neolithic builders. The earthfast stones, the uprights set directly into the ground, measured up to 12.2 metres in one dimension and reached heights between roughly 0.85 and 1.75 metres. Despite their scale, the arrangement did not correspond to any clearly recognised tomb type. De Valera and Ó Nualláin cautiously suggested it might be the heavily disturbed remnant of a court tomb, a style of communal Neolithic burial monument characterised by a roofless forecourt at one end and a covered gallery behind it, common across the northern half of Ireland. That identification was tentative, and the confusion between ancient uprights and later field clearance stones made confident classification impossible.

The site is no longer visible at ground level. Whether it was absorbed into pasture management, obscured by soil movement, or simply too fragmentary to survive surface recognition is not recorded. What remains is the name on the Ordnance Survey field maps, and the knowledge that something once stood here that was large enough, and strange enough, for people to call it a giant's work.