Souterrains, stone-built underground chambers or tunnels typically associated with early medieval settlement, were constructed across Ireland for purposes that are still debated, with theories ranging from food storage to places of refuge. This particular example is no longer accessible in any meaningful sense, its roof long since fallen in, but the outline of it remains legible in the landscape.

The structure was built using drystone technique, meaning the walls were laid without mortar, relying entirely on the careful placement of stone. It ran roughly seven metres in length and about two and a half metres in width, oriented along an east-west axis. It sat within the northern portion of a rath, the circular earthwork enclosure that would have formed the defended farmstead of an early medieval family or community. The earliest published reference to this souterrain appears in a 1914 account by Athy, suggesting it had already suffered significant collapse by the time anyone thought to write it down formally. What prompted that note, or what the site looked like then versus now, is not recorded.