That gap itself is telling. Enclosures of this kind, typically defined by a bank, ditch, or stone wall encircling a roughly circular or oval area, appear across Ireland in considerable variety. Some were farmsteads, some had ceremonial functions, and some blur the line between the two. Without further detail, An Goirtín Mór keeps its particular character to itself.

The name of the townland offers a small clue to the human geography of the place. The word goirtín is a diminutive of goirt, meaning a tilled or cultivated field, and the combination with mór, meaning big or great, carries that slight contradiction common in Irish placenames, where scale and affection become entangled in the naming. Mayo as a county has no shortage of such enclosures; the western seaboard landscape is layered with earthworks that have endured because the land was never intensively ploughed, preserving beneath blanket bog and rough pasture the outlines of lives lived here across several millennia. Whether this particular enclosure belongs to the early medieval period, the Bronze Age, or some other horizon is not yet recorded in any accessible source.