It measures roughly ten metres along its longer axis and rises to about 1.3 metres at its highest external point, enclosing a small central hollow just two metres across. A gap running approximately east to west splits the mound in two, and a small hummock about four metres to the south may represent further accumulated material from the same source. A stream runs immediately to the east, turns, and flows away to the south-west, which is precisely where you would expect to find this kind of monument.

A fulacht fia is a prehistoric cooking site, the most common type of ancient monument found in Ireland. The typical arrangement involved heating stones in a fire, dropping them into a water-filled trough to bring it to the boil, and using that trough to cook meat. The spent, cracked stones were discarded into a mound around the trough, and it is those accumulations, dark with ash and fire-shattered rock, that survive today. The proximity of running water was essential to the process, which is why fulachtaí fia cluster so reliably beside streams and in low-lying, waterlogged ground. This example at Poulnalour sits in exactly such a setting, on poached, clayey soil. In 1994, a map annotation by Tom Coffey recorded four fulachtaí fia at this location. When the site was inspected in 1999, only two could be identified in close proximity to one another, separated by about ten metres. Two further examples recorded roughly 125 and 145 metres away may account for the remainder of the original group of four, suggesting this was once a repeatedly used spot over a considerable stretch of prehistoric time.