This rock-cut souterrain, a type of artificial cave structure commonly found across Ireland, stretches for at least 12 metres through the bedrock, though its full extent remains unknown as much of it is now filled in and inaccessible. Two openings puncture the surface; the southwestern entrance may be a more recent addition, whilst the northeastern opening sits at a right angle to the main passage and features a traditional flagstone roof.

The construction technique reveals the considerable effort involved in creating these subterranean spaces. Whilst the northeastern section employs carefully placed flagstones for roofing, the remainder appears to have been laboriously tunnelled directly through the solid rock. A small hole on the western side of the northeastern entrance hints at the possibility of a side chamber, suggesting this souterrain may have been more complex than a simple linear passage. Such underground structures served various purposes in early medieval Ireland, from storage facilities and places of refuge to locations of ritual significance.

Today, the souterrain sits quietly amidst rough pasture land, its entrances offering only tantalising glimpses into what was once a fully functional underground complex. Like many of Ireland's estimated 3,500 souterrains, this example at Cowpark raises more questions than it answers about the daily lives and concerns of the people who carved it from the living rock centuries ago.