This is a souterrain, a type of dry-stone underground chamber or tunnel built during the early medieval period, typically beneath or beside a rath. A rath is a circular earthwork enclosure, usually associated with a farmstead of the early Christian centuries, defined by one or more earthen banks and ditches. The two features together, the enclosure above and the passage below, form a layered kind of occupation that was once common across Ireland but survives only patchily.

The souterrain here appears to be L-shaped, with a total measurable length of more than 11.6 metres. The longer arm, running roughly north-northwest to south-southeast, stretches some 6.4 metres but has almost entirely fallen in, with only a single roof lintel visible at its northern end. The shorter arm extends from the southern end of the western wall in a broadly east-west direction and runs approximately 5.2 metres, narrowing to about 0.9 metres in width. Three roof lintels protrude from the sod along this section, giving a sense of the original corbelled or lintel-covered roof that would once have covered the whole passage. The structure is described as inaccessible, which is unsurprising given the degree of collapse. Elsewhere within the same enclosure, a standing stone occupies the eastern sector, adding another layer of antiquity to what is clearly a site that saw use across a considerable stretch of time.

The lintels breaking the surface are the most tangible sign of what lies beneath, and for anyone who knows what to look for, their alignment across the grass makes the L-shaped plan almost readable from ground level. The site sits within a rath, so the low earthwork of the enclosure itself should be visible in the surrounding field, giving context to the scattered stonework within it.