They appear as low, horseshoe-shaped mounds, typically beside a stream or boggy hollow, and they date mostly to the Bronze Age, roughly 1500 to 500 BC. The standard interpretation is that they are cooking sites: a trough dug into the ground, lined with wood or stone and filled with water, which was then brought to the boil by dropping fire-heated stones into it. The burnt and shattered stones, discarded after use, form the mound itself. One such site sits in the townland of Poulataggle in County Clare, a quiet addition to a landscape that holds many such traces of early activity.

The name Poulataggle offers a small clue to the character of the place. In Irish, poll means a hole or hollow, and the second element likely refers to a notch or gap, suggesting low-lying or indented ground of the kind that fulachtaí fia consistently favour. These sites need proximity to water, and the choice of location was almost certainly practical rather than ceremonial, though some archaeologists have proposed that at least some mounds may have served for bathing, textile preparation, or brewing rather than, or as well as, cooking. The debate has not been settled, and Poulataggle, like most of its counterparts, keeps its original purpose ambiguous.