What it turned up instead was a scatter of broken, fire-cracked stone that had been lying quietly in the ground for roughly four thousand years. Archaeologists monitoring the works recognised it as a burnt mound, a type of prehistoric site found widely across Ireland and Britain, typically associated with the repeated heating of stones in fire and their use to boil water in a timber or stone trough. The stones crack under thermal stress and are discarded in a heap, gradually building up the characteristic mound shape over what may have been decades or centuries of use.

This particular mound sits on a slight north-west-facing slope and measures about 10.6 metres north to south and 5 metres east to west, with a maximum surviving depth of just 0.12 metres, making it a fairly thin spread. A modern field drain had already cut through its western edge before the excavation began in January 2017, and the mound itself extended beyond the boundary of the motorway land-take to the north-east, meaning only part of it could be investigated. No trough, pit, or other associated features were found within the excavated area, and no artefacts came to light either. What the site did yield was environmental evidence: charred wood in which oak was dominant, with some hazel also present. A radiocarbon date obtained from hazel charcoal placed the site's use somewhere between 2136 and 1950 BC, placing it firmly in the Early Bronze Age. The research was published by Whitty and Kavanagh in 2018.

The site is now beneath or beside the motorway corridor and is not accessible to visitors, though the remainder of the mound, still unexcavated, presumably survives in the ground to the north-east of where the road now runs.