It measures roughly eight metres across, and to a passing eye it would read as little more than a slight unevenness in the ground. Small patches of stony black soil break through the sod where grazing animals have worn the surface away. This is a burnt mound, and that dark, heat-fractured stone is the giveaway: these sites are defined by the accumulation of fire-cracked rock and charcoal-rich soil left behind by a process of repeated heating and quenching, likely used for cooking, bathing, or some form of industrial boiling. They are among the most common prehistoric monument types in Ireland, and they cluster especially in wet, low-lying ground, exactly the kind of setting this one occupies.

What makes the Greenwood mound particularly interesting is that it does not sit alone. Within roughly 220 metres, there are at least two further burnt mounds and a possible burnt spread. The full original extent of this particular mound is unclear, and cultivation ridges running on a north-east to south-west axis are still visible in the surrounding field, suggesting the land has been worked in different ways over a long span of time. The proximity of these sites to one another raises quiet questions about how the landscape around Bekan Lough was used, and by whom, across what may have been centuries of repeated activity in the same general area.