It measures seventeen metres north to south and eight metres east to west, rising only half a metre above the surrounding ground. To a casual eye it might be nothing more than a slight undulation in the field, but beneath that grass-covered surface lies a dense accumulation of burnt and fire-cracked stone, the unmistakable signature of a fulacht fia.

A fulacht fia is a prehistoric cooking site, typically Bronze Age in origin, where stones were heated in a fire and then dropped into a water-filled trough to bring it to the boil. The process left behind large quantities of shattered, heat-spent stone that gradually mounded up beside the trough over repeated use. These sites are extraordinarily common across Ireland, particularly in low-lying, damp ground close to water sources, which makes the location beside this spring entirely typical. What is less typical is the concentration here: this mound is one of a cluster of four fulachta fiadh recorded in the immediate area at Downing, suggesting the spot saw sustained or repeated activity rather than a single episode of use.