The site takes the form of a pointed oval enclosure, roughly thirty metres across on one axis and forty on the other, defined by two low earthen banks with a fosse, or ditch, running between them. Inside this enclosure, and taking up much of its interior, is a natural circular mound with a shallow saucer-shaped depression at its summit, most likely caused by quarrying at some point in the past.

What makes the place quietly compelling is the landscape it sits within. The ground around it is heavily saturated, and the working interpretation is that this was once a lake, with the mound rising above the waterline as a small island. That reading connects it to the crannóg tradition, a form of settlement common in early medieval Ireland in which artificial or partially artificial islands in lakes were used as defensible dwelling places. Whether this particular mound was ever built upon or simply occupied a position that made it strategically useful is not certain, but the configuration, a raised natural feature enclosed by banks and surrounded by wet ground, fits that pattern closely enough to suggest the comparison is not fanciful. By 1837, the Ordnance Survey Field Name Books were recording that the townland of Calliaghstown contained an ancient mound, which may well be this same feature, though the surveyors never flagged it formally on any edition of the six-inch map series.