These low, crescent-shaped or kidney-shaped mounds consist almost entirely of fire-cracked stones and charred material, typically found close to a water source. The working theory, broadly accepted though not without challenge, is that they represent Bronze Age cooking sites, where stones were heated in a fire and then dropped into a water-filled trough to bring it to the boil. The Irish term, fulacht fiadh, translates loosely as cooking pit of the deer, though some researchers argue the structures may have served other functions entirely, from textile processing to brewing.

Burnt mounds cluster heavily across Munster and are among the most frequently encountered prehistoric monuments in Clare. Most date to the Bronze Age, roughly between 1500 and 500 BC, though some examples fall outside that range. The characteristic mound builds up gradually from repeated use, as spent, shattered stones are shovelled aside after each firing and accumulate around the edges of the trough. What remains in the ground is essentially a record of that repetitive, practical activity, preserved not through any intention to memorise it but simply because broken rock and charcoal resist decay. The specific details of the Killulla example, its dimensions, its precise location within the townland, and any associated finds or features, are not yet fully documented in the available public record.