The arrangement looks, at first glance, like a geological accident, as though a retreating glacier simply left the rocks balanced there. But this is a boulder-burial, a Bronze Age funerary form in which a massive capstone is deliberately raised above a pit, creating a low, heavy monument that sits somewhere between a dolmen and a grave marker, and these two examples are among the better-documented specimens of that type in Ireland.

Excavations carried out in 1988 by Dr W.F. O'Brien revealed the details of what lies beneath. The larger of the two boulders, roughly 1.8 metres by 1.6 metres and over a metre thick, rests on three support stones above a central pit. Charcoal fragments recovered from that pit returned a radiocarbon date of 3080 plus or minus 35 years before present, placing the monument's construction in the later Bronze Age, somewhere around the eleventh or twelfth century BC. Seven narrow stake-holes were found surrounding the monument, suggesting that some kind of timber structure or enclosure once stood around it. A second, slightly smaller boulder burial sits just 3.8 metres to the east, its sub-rectangular cover stone supported on three stones placed over a large backfilled pit. Neither excavation recovered human bone or artefacts in direct association with the monuments, which leaves their precise function open to interpretation. The absence of skeletal remains is not unusual given the acidic soils of the region, which dissolve organic material over millennia, but it means the connection to burial practice rests more on the monument type than on direct physical evidence.