The souterrain, as these underground stone-lined passages are known, was built as part of a rath, the kind of circular earthwork enclosure that early medieval farming communities across Ireland constructed as defended homesteads. This one is bivallate, meaning it had two concentric banks of earth rather than the single ring more commonly encountered, which suggests a degree of status or perhaps a particular need for security on the part of whoever lived within it.

The entrance to the souterrain sat in the northern part of the rath's interior, and the tunnel beyond it ran further northward beneath the ground. Souterrains were typically used for cold storage, refuge, or both, and their entrances were often deliberately narrow or awkwardly angled to slow any intruder. The Baltovin example was documented in C. Toal's North Kerry Archaeological Survey, published in 1995, at which point the landowner could still describe the tunnel's direction from memory or observation. By the time of more recent recording, however, the feature had been completely filled in, leaving the rath itself as the only visible trace of what was once a more complex site.

What remains above ground is a sub-circular earthen enclosure, its inner area still legible as a raised or defined space within the landscape. The double bank, where it survives, is the detail worth looking for, since that second ring of earth is what distinguishes this rath from the many single-banked examples scattered across Kerry and the wider country.