It measures roughly 8.5 metres north to south and 12.3 metres east to west, rising to about 1.4 metres at its highest point. A depression in the northern sector, approximately 4.5 metres by 2.6 metres, most likely marks the site of the original trough. What makes this quiet mound remarkable is not just what it is, but how many of its kind have gathered here: five further examples of the same type have been identified along the same stream, within 200 to 300 metres to the east and south-east.

A fulacht fia, sometimes called a burnt mound, is among the most common prehistoric monuments in Ireland, yet the mechanics behind one are striking. The typical arrangement involved a timber-lined trough sunk into wet ground and filled with water, into which fire-heated stones were dropped repeatedly to bring the water to a boil. The spent, shattered stones were then raked aside, gradually building up the characteristic horseshoe or kidney-shaped mound that surrounds the trough on three sides. Most fulachta fia date to the Bronze Age, broadly between 1500 and 500 BC, though some are earlier or later. Their purpose has been debated at length, with cooking, brewing, bathing, and textile processing all proposed by archaeologists over the years. The site at Rathlogan fits the classic profile closely, with its proximity to running water and boggy ground being exactly the conditions these monuments seem to favour.

The clustering of six sites along a single modest stream is particularly notable. It suggests repeated or prolonged use of this small valley over time, with communities returning to the same reliable water source across generations. Whether the individual mounds represent different episodes of activity spread over centuries, or something more concentrated, the stream corridor at Rathlogan preserves an unusually dense record of this form of prehistoric practice in a single, unassuming landscape.