Six Neolithic houses buried beneath a Kildare sand and gravel quarry is not the kind of discovery most people associate with routine extraction work. Yet that is precisely what happened at Corbally, where the proposed expansion of a large pit triggered two separate phases of excavation, the first in 1997 and 1998, and the second in 2001, each turning up a cluster of rectangular timber structures dating to the fourth millennium BC, somewhere between five and six thousand years ago.

The 2001 excavation, carried out under licence by Tobin, uncovered three further houses sitting roughly a hundred metres south of the original trio. Two of them were reasonably well preserved. House 4 measured ten metres east to west and seven metres north to south, and its eastern wall trench told a layered story across at least three distinct phases of use. The earliest phase involved deep foundation trenches set with upright oak planks, a method of wall construction that is unusual and technically accomplished for the period. A hearth sat within the eastern wall itself, apparently in continuous use across the life of the building. When fire damaged parts of the structure, the occupants replaced them with lighter prefabricated panels slotted into recut sections of the original trenches. Among the finds were a polished stone axe, flint scrapers, struck flint flakes, and quantities of Neolithic pottery, along with seeds, chaff, and hazelnut shells that point to the kind of domestic agricultural activity one might expect from early farming communities. House 5 was smaller, at seven metres by five, and its western wall trench survived well enough to preserve the actual stumps of upright oak planking. Post-holes inside the structure give a rare indication of how the roof was framed. A finely worked chert arrowhead was among the few artefacts recovered. House 6 proved more ambiguous; features that looked structural from above became harder to interpret during excavation, and may represent outbuildings or work areas associated with House 5 rather than a dwelling in its own right. Environmental samples from the area showed a strong concentration of wheat seeds and chaff, suggesting that processing grain was a significant activity on this part of the site.

Lazy-beds, the raised cultivation ridges left by later agricultural activity, had cut across and damaged several of these structures, a reminder of how many thousands of years of farming separated their construction from their discovery. Nothing survives above ground at Corbally today; what made the site legible was the negative evidence left in the soil, the ghost shapes of trenches, plank impressions, and post-holes that only became visible once the overburden was removed.