In 2004, archaeologists Brian O’Donnchadha and Rob Lynch fully excavated this site ahead of the N15 Bundoran-Ballyshannon By-Pass construction. What they uncovered in this low-lying valley, characterised by boggy pasture and poorly drained stony silty clay, was an intriguing combination of a linear earthwork and what appears to be an ancient furnace.

The furnace itself is a remarkable piece of engineering from its era. Carved directly into the natural subsoil, it stretches approximately 5.3 metres from east to west and consists of three distinct sections. At the elevated eastern end, archaeologists discovered an area of intense burning, filled with charcoal-rich deposits and heat-affected mudstone; clear evidence of the high temperatures once generated here. The central portion features a carefully constructed area of built stones, with steep, irregular sides designed to accommodate stones ranging from 0.1 to 0.47 metres in size. At the western end, a drainage gully angles slightly eastward, likely designed to channel away water or other liquids from the main furnace body.

Charcoal analysis from the site revealed the use of oak and birch wood as fuel, whilst radiocarbon dating placed the furnace’s operation somewhere between the late Iron Age and early medieval period. The linear earthwork, positioned immediately south of the furnace, adds another layer of mystery to the site’s function. Whether this was a centre for metalworking, pottery production, or some other industrial activity remains an intriguing question for historians and archaeologists studying Ireland’s ancient technological capabilities.