Earthworks is a broad term covering a wide range of human-made or human-modified landforms, from the banks and ditches of enclosures and ringforts to the remnants of field systems, burial mounds, or defensive boundaries. Without knowing which category this particular feature falls into, it occupies a curious position, acknowledged by archaeology but not yet described to the public in any detail.

Breaghwy is a townland in the Castlebar area of County Mayo, a county whose landscape carries layer upon layer of prehistoric and early medieval activity. Mayo has a particularly dense concentration of earthwork monuments, many of them poorly understood, some stumbled upon in improved pasture or upland terrain. The specific earthwork here has been noted in the national record but the details that would allow us to say what it is, when it was made, or by whom, remain unavailable for now.