It is not dramatic in scale, rising less than a metre at its highest point, but its form is precise enough to suggest purpose rather than accident. This is a fulacht fia, a type of prehistoric cooking site found in considerable numbers across Ireland, typically dating to the Bronze Age. The usual interpretation is that water was heated in a sunken trough by dropping fire-heated stones into it; the shattered, heat-fractured stones were then piled up around the trough, gradually building the characteristic mound that survives today.

The Ballyryan example measures roughly 9.1 metres east to west and 8.7 metres north to south, opening to the west. The bulk of the mound sits to the east, where it reaches between 0.8 and 0.9 metres in height and extends to a width of about 5.1 metres. Moving north and south, the arms of the horseshoe narrow and lower, tapering as they approach the open western end. Within that opening, an oval area measuring approximately 2 to 5 metres east to west and around 2 metres north to south is thought to have held the trough itself. A line of stone running along the inner western edge of the mound, visible from the north and from the northeast around to the south-southwest, appears to have served a practical purpose, acting as a kind of retaining edge to keep the accumulated mound material from collapsing inward. A smaller, lower spread of material sits a metre or two further to the west, a secondary accumulation that adds a little more complexity to the site's layout. What makes the location particularly interesting is its proximity to another, older monument: an unclassified megalithic tomb lies roughly 60 metres to the northwest, a reminder that this corner of Clare was being shaped and used by people across a very long span of prehistory.