That absence is, in its own way, the most interesting thing about it. When the cist was discovered in 1961 and examined by the National Museum of Ireland, its interior was already empty, leaving open the question of whether it had ever held a burial at all, or whether whatever it once contained had long since disappeared.

A cist is a prehistoric burial box, typically constructed from flat stone slabs and used to inter the remains of the dead, often in a crouched position, sometimes accompanied by a ceramic vessel or small personal objects. This example is modest in scale, measuring roughly 73 centimetres along its longer internal axis and 61 centimetres across, with a depth of around 40 centimetres. Six stone slabs make up its structure, two on each of the long sides, with the remaining slabs closing the ends. It would originally have been covered by two capstones, but these were displaced, presumably some time before the formal discovery, by agricultural ploughing. John Waddell, whose 1990 survey of Irish Bronze Age burial practices catalogued the site, recorded it among a wider pattern of such monuments across the country, though the missing capstones and empty interior mean Eardownes Great contributes more of a question than an answer to that record.