It is, in fact, a fulacht fia, one of the most common yet persistently mysterious monument types in the Irish landscape. These are the remains of Bronze Age cooking sites, or so the prevailing theory goes: a trough would be dug into the ground, filled with water, and heated by dropping fire-cracked stones into it until the water boiled. The shattered, blackened stones were then raked out and piled to the side, accumulating over repeated use into the characteristic horseshoe or kidney-shaped mounds that survive to this day. The one at Liscahane is roughly circular, measuring about 16.5 metres north to south and 19.2 metres east to west, and rises to just 0.65 metres at its highest point, a gentle saucer shape barely interrupting the ground surface.

The waterlogged, marshy setting is entirely typical. Fulachtaí fia, to use the Irish plural, are almost always found near a reliable water source, whether a stream, a spring, or simply ground that holds moisture well. The burnt and fire-shattered stone that makes up the mound at Liscahane is the accumulated debris of that ancient process, preserved here because wet, acidic ground is, paradoxically, often better at protecting organic and archaeological material than drier soils. Thousands of these sites are known across Ireland, making them among the most frequently recorded prehistoric monument types on the island, yet their exact social function remains a matter of debate. Cooking is the most widely accepted explanation, but some researchers have proposed uses ranging from communal bathing to textile processing.