This is a souterrain, a type of dry-stone underground structure built during the early medieval period in Ireland, typically used for food storage, refuge, or both. What makes this one quietly compelling is how much of its architecture survives in the wreckage: not a simple void in the earth, but a sequence of chambers and connecting passages, some still roofed with their original lintels, others robbed of their stonework and now visible only as grassed-over depressions.

The souterrain sits in the south-western quadrant of a rath, the circular earthen enclosure that would once have been the fortified farmstead of an early medieval family. Raths, sometimes called ring forts, were the most common settlement type in early medieval Ireland, and souterrains were frequently built within them, accessed from inside the enclosure. Here, the underground complex runs on a roughly north-west to south-east axis and comprises at least two main passages with a connecting creep, a deliberately narrow crawl-through opening designed to slow or deter intruders. One passage has collapsed into an oval depression measuring approximately 5.4 metres long and 0.6 metres deep. At its north-western end, a short intact section leads through a creep just 0.7 metres wide, roofed by two lintels, into a further passage of around 4.8 metres, itself largely collapsed and stripped of its roof stones. Beyond that, an opening measuring 0.8 metres in both width and height gives access to an intact stone-built chamber, still roofed with lintels and extending northward, though its full extent could not be examined. A ruined field wall cuts across the western edge of the site, a reminder of the centuries of agricultural activity that have gradually obscured what was once a carefully engineered underground space.