The burnt spread, measuring 6.4 metres in length and standing 0.9 metres high, only came to light when drainage works cut into the east bank of the stream and exposed its sloping face. Burnt material has also scattered across the opposite bank, suggesting either the spread of a single episode or repeated use of this waterside location over time.

What exactly produced these concentrations of fire-altered material is not stated in the available record, but burnt spreads of this kind are frequently associated with fulachta fiadh, a type of prehistoric cooking or industrial site found across Ireland in which water was heated by dropping fire-cracked stones into a trough or pit. The characteristic mound left behind is composed of that shattered, heat-reddened stone and charcoal-rich soil. They tend to cluster near water sources, which made the bank of the Slievenaneav stream a logical and practical setting. Notably, a second burnt spread lies approximately 90 metres to the north-west, suggesting this stretch of low boggy ground was returned to repeatedly, perhaps across generations.