It came to light not through a formal excavation or a chance encounter with masonry, but through the mundane act of digging a hole for a tree. A concentration of burnt stones and charcoal fragments turned up in the pit, close to a stream, in the garden of a newly built house. The landowner called in an archaeologist, the significance of the find was confirmed, the pit was backfilled, and the grass was allowed to grow back over it. The full extent of what lies beneath remains unknown.

What was found belongs to a class of monument known as a burnt mound, one of the most common yet least visually dramatic prehistoric features in the Irish landscape. Burnt mounds typically consist of large quantities of fire-cracked stone and charcoal, the accumulated debris of repeated heating. The stones were heated in a fire and then dropped into a water-filled trough to bring it rapidly to the boil, a process repeated until the stones cracked and were discarded in a heap. Their precise function is still debated, with proposals ranging from cooking to bathing to industrial processes such as hide-working. They are almost always found near water, which makes the proximity of a stream at Knockshanbally entirely consistent with the type. Most date to the Bronze Age, roughly 2000 to 500 BC, though some examples fall outside that range. Because burnt mounds are often low and spread across a wide area, they tend to survive unnoticed, sometimes for millennia, until ground disturbance brings them to the surface.

There is nothing to see at Knockshanbally today. No mound rises above the turf, no marker indicates the spot. The site exists now as a protected but largely invisible presence, its boundaries undefined and its contents untouched since the tree-planting pit was closed over.