They stand between half a metre and one and a half metres tall, arranged in a rough east-west line, with two stones at the western end turned to face north-south instead, and a single outlying stone placed eight metres to the north of the row. When the tide comes in, only their upper halves remain visible above the surface. It is a quietly disorienting sight, the kind that rewards a patient observer who happens to be there at the right moment.

The stones are thought to be the remnants of a submerged field boundary, that is, a wall or demarcation line that once divided agricultural land now lying beneath sea level. The geographer Frank Mitchell, writing in 1976, identified the alignment as probable evidence of this kind of feature. The implication is significant: at some point in the past, this stretch of coastline was dry land, worked and divided by people who needed to mark out where one holding ended and another began. Sea-level rise and coastal change have since swallowed that landscape, leaving only the stones as evidence that fields once existed here. The precise age of the boundary is not recorded, but submerged field systems along the Irish coast are generally associated with prehistoric or early historic periods, when relative land levels were different from today.

The stones are on White Strand at the inner end of Crookhaven Bay, and timing a visit around low tide is essential if you want to see the full row rather than just a scattering of wet tips protruding from the water. The outlying stone to the north, standing roughly 1.3 metres tall and relatively slender at 0.7 metres wide, is worth locating separately; its north-south orientation, at odds with the main alignment, hints at some more complex arrangement that the sea has long since obscured.