Enclosures of this kind are among the most common yet most varied features of the Irish countryside. The term covers everything from the earthen banks of an early medieval farmstead to the stone-walled boundaries of a prehistoric settlement, and without further documentation it is difficult to say precisely what this one represents or how old it might be.

Cornagashlaun is a small townland, and like many in Mayo it carries a name that encodes something of the landscape itself. The county is exceptionally rich in earthworks, field systems, and enclosures that span thousands of years of continuous habitation, many of them still visible as low, grass-covered ridges or as cropmarks visible only from the air. The enclosure here has been catalogued as a monument, which means it has been identified and given protected status, but the supporting detail that would allow a fuller picture has not yet been made available in any accessible public form.