In the townland of Derry in County Galway, a hachured symbol on the 1944 to 1945 revision of the Ordnance Survey six-inch map suggested the presence of some feature worth noting. When someone finally went to look in 1984, what they found was a disused gravel pit, overgrown and sunken into the surrounding pastureland.

The pit is post-1700 in date, which places it outside the scope of archaeological protection in Ireland, where the threshold for formal recording generally falls at that year. Gravel pits of this kind were working features of the rural landscape, dug to extract material for road surfacing or farm tracks, and then abandoned once the immediate need passed or the supply ran thin. The hachures on the OS map, short radiating lines used to indicate a hollow or depression in the terrain, were doing their job accurately enough; they just could not convey that what lay beneath them was ordinary and modern rather than ancient.