Look more carefully, though, and the logic of it begins to emerge: an oval enclosure, carefully shaped, its interior sloping almost imperceptibly downward toward its own centre, the surrounding bank still holding its form after more than a thousand years of Irish weather and grazing animals.

This is a rath, the most common type of ringfort in Ireland, typically dating from the early medieval period, roughly the sixth to the twelfth centuries, when they served as the enclosed farmsteads of farming families. They were not primarily military structures, despite the word "fort"; rather, the bank and ditch provided a boundary that kept livestock in and wolves or opportunistic raiders out. The example at Killeany Beg is oval in plan, measuring approximately 21.5 metres north to south and 24 metres east to west. Its earthen bank survives to an internal height of around 0.45 metres and an external height of 0.65 metres. Beyond the bank runs an external fosse, a drainage or defensive ditch, roughly 2 metres wide and 0.35 metres deep, running from the south-east around to the north-north-east. At the south-west and south-east, a low counterscarp bank, the secondary bank on the outer edge of the ditch, remains visible at around 0.15 metres high and 3 metres wide. The site was documented by Denis Power and uploaded to the national record in August 2011.

The monument sits within working pasture, so the ground underfoot is soft and uneven, and conditions underfoot will depend heavily on recent rainfall. The earthworks are subtle enough that approaching with an Ordnance Survey map or a GPS reference is worthwhile; the low banks can be easy to read once you are standing inside the enclosure and feel the gentle bowl of the interior around you, but harder to pick out from a distance across open farmland. As with any site on private agricultural land, checking access arrangements locally before visiting is advisable. The fosse section running from south-east to north-north-east is perhaps the most legible feature on the ground, offering the clearest sense of how the enclosure was originally delineated.