Road schemes have an odd habit of turning up the past just before they bury it. When topsoil-stripping began for the Celbridge Interchange in Castletown, Co. Kildare in 2001, the machinery uncovered what appears to be the remnants of a small agricultural operation from the Early Christian period, roughly the fifth to twelfth centuries. Tucked into the ditch of an enclosure that also contained a ringditch, a circular or penannular earthwork whose original function remains uncertain, was a stone-built kiln that had once been used to dry grain before milling.

Corn-drying kilns were a practical necessity in the damp Irish climate. Grain harvested in wet conditions could not be milled cleanly, and so it was spread above a low fire in a stone-lined chamber to draw out the moisture first. The excavation here, carried out under licence 01E0669, confirmed this function in two ways: soil samples taken from the kiln interior still contained grain residues, and part of a quernstone, the hand-operated grinding stone used to process the dried grain into flour, was found within the kiln structure itself. A short distance away, a large pit filled with burnt material and an iron knife blade was also uncovered; archaeologists have suggested this pit may be contemporary with the kiln, possibly representing domestic or craft activity associated with the same settlement phase. Taken together, the finds point to a small but self-sufficient farming community working this corner of Kildare somewhere in the Early Christian centuries, going about the entirely ordinary business of drying and grinding their harvest.