What makes it quietly puzzling is not its size, roughly 45 metres in diameter, but what it lacks: there is no visible fosse, which is the ditch that typically runs alongside an earthen bank to form a defensive or boundary circuit, and no discernible entrance. Most enclosures of this kind betray at least a gap in their perimeter where people and animals once passed through. Here, the bank or scarp, rising between one and one and a half metres on the exterior, runs continuously around the site, reinforced by hedging on nearly all sides, with only a faint, almost imperceptible trace on the east-northeast to east-southeast arc.

Embanked enclosures of this form appear across Ireland in considerable variety. Some were raths or ringforts, the enclosed farmsteads of early medieval Ireland, typically dating from roughly the sixth to the twelfth centuries. Others served ceremonial or pastoral functions, and without excavation it is rarely possible to say which category a given example falls into. The absence of a fosse at Rickardstown is notable: ringforts were most commonly constructed by throwing up a bank from a surrounding ditch, so a site with no such ditch either had a different constructional method or a different purpose entirely. The raised, circular profile, sitting slightly proud of the surrounding land, suggests the bank was built up rather than simply scraped from the ground beside it.