Not a wall, not a field boundary, but a low earthen monument that most people would walk across without a second thought. It was not a ground-level survey that brought it to wider attention, but a satellite image, one taken in March 2019, in which the subtle geometry of a ring-barrow became legible in a way that the overgrown terrain beneath would not easily allow.

A ring-barrow is a burial monument of prehistoric date, typically consisting of a low central mound enclosed by a circular bank and ditch. They are found across Ireland and Britain and are generally associated with the Bronze Age, though the tradition of marking the dead with earthen enclosures spans a considerable stretch of prehistory. The example at Carheenshowagh measures roughly fifteen metres in diameter at its widest point, a modest but coherent form that the aerial perspective renders as a near-perfect circle against the surrounding pasture. It was identified and reported by Jean-Charles Caillère, whose reading of the Google Earth imagery drew attention to a feature that would otherwise have continued to sit unrecorded in the field.