The discovery came not from a dedicated excavation but from routine topsoil stripping ahead of development, carried out under licence 02E0330. What first appeared as a spread of dark soil measuring 12 metres by 10 metres revealed itself, once cleaned back, to be only the uppermost and central portion of something far larger. The rest had been quietly buried under clay carrying pottery and glass of recent date, concealing its true extent until that machinery moved across the field.

What lay beneath was a fulacht fia, a type of prehistoric cooking site found in considerable numbers across Ireland, typically comprising a mound of fire-cracked stone, a hearth, and a trough or pit into which water was poured and heated stones dropped to bring it to the boil. The Carmanhall example, recorded by Breen in 2004, preserved several distinct layers and lenses within the spread, suggesting repeated use over time rather than a single episode. Underneath those layers were four shallow depressions, possibly artificial in origin, and one more clearly defined rectangular pit measuring 2.56 metres long, 1.2 metres wide, and 0.8 metres deep, proportions consistent with the kind of trough associated with fulacht fia activity. Complicating the picture further, a wall footing had been dug into the spread at some later point, forming three sides of a rectangle measuring 7 metres by 4.5 metres, adding a post-prehistoric layer of use to a site that had already been partially obscured by the ornamental pond installed sometime in the eighteenth or nineteenth century.

Carmanhall is now a suburban and commercial part of south Dublin, and the site itself sits within a landscape that has changed substantially since the excavation was carried out. There is no public monument or marker here, and the archaeology has long since been recorded, archived, and built over. Its interest lies less in visiting and more in what it represents: the routine way in which prehistoric sites surface, briefly, during the groundwork for office parks and housing schemes, captured in licence reports before the ground closes over them again. The compiled record, assembled by Geraldine Stout and Padraig Clancy, preserves what the development would otherwise have erased entirely.