Before construction work could begin at Castleview, archaeologists uncovered the remains of what appears to be a corn-drying kiln, a structure used in early medieval Ireland to dry harvested grain before milling or storage. Given Ireland's damp climate, such kilns were a practical necessity, and their remains, typically channels and pits scorched by repeated firing, turn up with some regularity on excavations. What makes this particular site unusual is not just the kiln itself, but the layered accumulation of activity surrounding it.

Excavator McCarthy interpreted a stone-lined linear feature, measuring roughly 3.54 metres long, 0.63 metres wide, and 0.4 metres deep, as a probable kiln flue, the channel through which heat was directed. It lay within a broad area of burning, and at its south-western end it cut into a subrectangular pit containing sand, charcoal, and small stones, suggesting the feature had been dug through even older deposits. A second pit nearby, filled with charcoal-flecked sand, heat-shattered stones, and ash, points to sustained and repeated use of fire in this area over time. The cluster of finds does not stop there. Within the immediate vicinity, excavations also revealed a second similar feature, another probable early medieval corn-drying kiln, and a fulacht fia, a type of Bronze Age cooking or industrial pit that typically involved heating stones in water. Taken together, the site represents centuries of human activity on the same small patch of ground, each layer of burning partially obscuring and cutting into what came before it.