On the 1933 edition of the Ordnance Survey six-inch map covering Ballyglass in County Galway, a cluster of dots marks a spot that invites speculation; dots on these maps could indicate any number of features, earthworks among them. When someone finally went to look in 1983, half a century after the cartographers had recorded whatever they saw, it turned out to be a quarry, a working or worked-out cut in the landscape where stone had been extracted at some point after 1700.

That date matters in a particular way. Irish archaeological classification draws a firm line at AD 1700, before which a site falls under the scope of formal archaeological survey and protection, and after which it generally does not. This quarry at Ballyglass sits on the modern side of that boundary, which places it outside the category of protected archaeological monuments despite its clear age and its presence on a map that is itself now nearly a century old. It is a small illustration of how heritage categories work in practice, and of how much of the post-medieval landscape quietly goes unclassified. Quarrying was widespread across rural Ireland from the eighteenth century onward, supplying stone for field walls, road surfaces, and the foundations of the farmhouses and outbuildings that still define the Connacht countryside.