They are almost nothing to look at. Each measures somewhere between forty and fifty centimetres across, with a maximum depth of just four centimetres, and the soil filling them is a black silty clay threaded through with very fine fragments of burnt bone. They are shallow enough to miss entirely, and for a very long time, that is precisely what happened.

The pits, catalogued as BGE 2/29/1, came to light not through a dedicated excavation but as a byproduct of infrastructure. During work on the Bórd Gáis Éireann Curraleigh to Limerick gas pipeline in 1988, archaeologist M. Gowen recorded this cluster of three pits sitting within five metres of one another. Cremation pits of this kind are a relatively common find in Irish prehistory; they typically represent the deposit of burnt human remains after a cremation pyre, sometimes placed with grave goods, sometimes not. What makes Ballygrennan quietly notable is the scale, or rather the lack of it. The pits are so shallow and so small that they read less as formal burial monuments and more as modest, deliberate acts, a handful of charred remains placed into the ground and covered over. The precise date of the pits is not recorded in the available sources, but this type of feature is generally associated with the Bronze Age in Ireland.

There is nothing to see at ground level today, and this is not a site with a car park or an information board. It sits in working farmland, and access would require both local knowledge and the landowner's permission. The value here is less in a visit than in the knowledge that the landscape around Limerick, seemingly unremarkable from a passing car window, has been interrupted at moments like this one, where the laying of a gas pipe briefly exposed something placed in the ground thousands of years ago and then forgotten entirely.