Around ten metres across, this small circular enclosure is defined by a fosse, a ditch cut into the earth, and the only way to see it now is from above, where differences in soil moisture and crop growth betray the buried outline as a cropmark on satellite imagery.

Ring-ditches of this kind are generally understood to be the remains of prehistoric funerary or ceremonial monuments, the enclosing ditches of round barrows whose earthen mounds have long since been levelled by centuries of agriculture. The Modreeny example was identified and reported by Jean-Charles Caillère, who spotted it through satellite imagery on Apple Maps. What makes the find quietly interesting is that it does not stand alone. A second ring-ditch of comparable character lies approximately fifteen metres to the south-east, the two cropmarks sitting side by side in the same tillage field, suggesting this corner of Tipperary may once have held a small cluster of burial monuments rather than a solitary one.