This one, on a north-east-facing slope at Aghavrin in County Cork, is remarkable chiefly for having disappeared. What was recorded here is a burnt spread, a term archaeologists use for a concentration of fire-cracked stones and heat-blackened soil, typically the residue of a fulacht fiadh, an ancient cooking site where water was boiled by dropping heated stones into a trough. These features are among the most common prehistoric monuments in Ireland, yet they are easily missed, and just as easily lost.

The spread came to light in 2001 when the field was ploughed, bringing dark-coloured soil to the surface. Local people noted its presence, and it was flagged as a possible burnt spread. When archaeologists returned in 2004, the field had gone back to pasture, and no trace of the feature could be found. It had either been obscured by grass cover, or the ploughing itself had disturbed and scattered whatever deposit remained. The site sits in what is now grazing land, on a slope that faces north-east, a common orientation for fulacht fiadh sites, which are often found near water sources in low-lying or sloping ground.

What the Aghavrin spread illustrates, quietly, is how much of the archaeological record exists in a kind of conditional tense. Seen once, unverified, then gone. The plough that revealed it may also have been what finally undid it.