When a hachured area appeared on the 1929 edition of the six-inch OS map for Gilkagh in County Galway, it carried just enough ambiguity to invite speculation. A disused quarry, perhaps, or some remnant earthwork of older origin.

When the site was inspected in 1984, the answer turned out to be rather more mundane: a disused gravel pit. Gravel extraction of this kind was common across rural Ireland, particularly in areas of glacial drift where surface deposits of sand and gravel were plentiful and easily worked. Small local pits supplied material for road maintenance and farm use, and when they were exhausted or no longer needed, they were simply abandoned. The Gilkagh pit had been out of use long enough by 1929 that the mapmakers recorded it only as a topographic irregularity, its original purpose no longer legible from the surface alone.