They are not ancient burial monuments in the conventional sense, though they carry the Irish word for graveyard in their name, Roilig Mhuire, meaning Mary's Cemetery or Our Lady's Burial Ground. They are penitential stations, stopping points along the Turas, the traditional pilgrimage circuit of Croagh Patrick, where walkers pray, circle the mounds, and add stones to the already considerable mass of loose rock that has accumulated over centuries of devotion.

The largest of the three cairns measures roughly 12.6 metres along its longer axis and rises to about 1.9 metres in height, pear-shaped when viewed from above. The two companion cairns sit just 3 metres and 10 metres to the north-east. What makes them visually distinctive is their outer surface: rather than bedrock or consolidated fill, each cairn is mantled in small loose stones deposited by pilgrims over generations. The scatter of stone around the base of each mound is not random erosion but the cumulative product of that same activity, stones sliding down from the outer layer as new ones are placed on top. The cairns are, in a sense, still being built.