These stone-built structures, typically resembling a squat bowl or draw-kiln set into a hillside, were used to burn limestone at intense heat, producing quicklime that farmers spread on acidic soils to improve fertility. The practice was widespread from the seventeenth century onward and represented a significant local industry in many rural townlands, yet the kilns themselves are so thoroughly embedded in field boundaries and hedgerows that most people walk past them without a second glance.

The Tirboy kiln sits within a townland whose name, like many in Connacht, carries traces of older Gaelic geography. Beyond its location in County Galway, the specific history of this particular structure, its construction date, the families who operated it, and the period during which it was in active use, remains to be fully documented. What can be said with confidence is that lime kilns of this type were communal necessities as much as private enterprises. Farmers would haul cartloads of limestone and fuel, often turf or culm, to the kiln, burn the stone over several days, and then rake out the resulting quicklime for spreading. The labour involved was considerable, and kilns were rarely built unless the surrounding land genuinely warranted the effort.