On the western foothills of the Monavullagh Mountains in County Waterford, three conglomerate stones stand in a short line across level ground, their Irish name, Lios na dTrí gCloch, translating roughly as the fort or enclosure of the three stones. A stone alignment is a prehistoric monument form found across Ireland and Britain, typically a row of standing stones whose original purpose remains debated, with theories ranging from astronomical sighting lines to ceremonial processional routes. What makes this particular example quietly compelling is the variation among the three stones themselves, each one distinct in shape despite standing within a total span of just 4.7 metres.

The alignment runs NE-SW, and the stones change character as you move along it. The northeast stone is the lowest of the three, reaching 0.65 metres in height, with a rectangular cross-section and a rounded top. The central stone rises to 1.25 metres and carries a crested top. The southwest stone is the tallest at 1.6 metres, square in cross-section, and comes to a point. The spacing is uneven too, with a gap of 1.6 metres between the northeast and central stones, and only 0.7 metres between the central and southwest stones. Beside the alignment to the southeast lies a possible fallen outlier, a larger stone measuring 1.85 metres in length, though it is known to have been moved to its current position rather than fallen in place. Approximately 80 metres to the west-southwest, there is a possible embanked enclosure, a low earthwork defined by a raised bank, which may or may not have had a relationship with the stones. The site was already recorded on the Ordnance Survey's six-inch map of 1840 within a small enclosure, and was noted by the Reverend P. Power in 1898 in his survey of County Waterford antiquities.