Beneath the undulating low-lying ground at Newcastle, excavators found the faint outline of a kiln, invisible at the surface, preserved only in the stained layers of subsoil beneath it.

The feature was uncovered and fully excavated in August 2002 as part of a programme of archaeological resolution ahead of the motorway's construction. What emerged was a subrectangular cut, roughly 3.7 metres east to west and 1.6 metres north to south, sunk no more than 26 centimetres into the subsoil. A kiln of this kind was essentially a managed fire-pit, used to dry grain or process other materials through controlled heat; the dense charcoal deposits found at the eastern end, and a second charcoal layer interpreted as the remains of the fire-pit's roof, are characteristic of how such structures functioned. Four unburnt stake holes near the centre suggest some kind of timber framing above. Radiocarbon dating placed the kiln's use somewhere between AD 1050 and 1270, broadly the early to high medieval period, while a nearby hearth returned a date of AD 980 to 1170. A furnace bottom, a separate but related feature, lay roughly 80 metres to the east, suggesting this part of the landscape was a working area of some kind rather than an isolated installation. The excavations were carried out under licence by R. O'Hara and are reported in detail in a volume on the archaeology of the Boyne floodplain published in 2008.