They are fulachtaí fia, a type of Bronze Age cooking site found in considerable numbers across Ireland, typically consisting of a horseshoe-shaped mound of fire-cracked stone surrounding a water-filled trough. The idea was straightforward: stones were heated in a fire, dropped into the trough to bring the water to a boil, and used to cook meat. What makes the Dromthacker examples interesting is that one of them does not quite fit the standard pattern, which raises questions about how these sites were actually used and how much variation existed within what we tend to treat as a single tradition.

The larger of the two mounds sits in waterlogged ground and takes an oval form, measuring roughly 14 metres north to south and 10 metres east to west, rising to about 0.75 metres. Beside it is a sub-rectangular depression, approximately 12.5 metres long and 4.6 metres wide, sunk to an average depth of around half a metre. Excavation carried out under licence 97E0022 uncovered what appears to be a trough pit within this depression, consistent with how fulachtaí fia typically functioned. The second, smaller mound to the west is only 6.7 metres in diameter and 0.5 metres high, and its shape does not conform to the classical fulacht fia form. It had already been disturbed before excavation took place, but a spread of fire-shattered stone some 4 metres across was found at the site, suggesting intensive burning activity had occurred there. Michael Connolly, writing in his 2008 doctoral thesis on prehistoric settlement in the Lee Valley area of Kerry, noted the ambiguity while still considering it a possible candidate for the same site type.