The enclosure measures just under twelve metres across, its boundary formed by the remains of a drystone wall, a type of construction that uses no mortar, relying instead on carefully selected and stacked stones to hold its shape. That wall has long since fallen, but enough survives to trace the full circuit, with the best-preserved section running from the north-west around to the east, where an inner and outer row of upright slabs can still be made out. Elsewhere, a low bank and irregularly spaced stones continue the line toward the north-west, giving the whole thing a slightly uneven, organic quality that is typical of early field and settlement enclosures across Kerry.

Circular enclosures of this kind are a recurring feature of the Irish archaeological landscape, and while their precise function can be difficult to establish without excavation, they are generally associated with early agricultural or pastoral activity, sometimes with settlement, and occasionally with more ceremonial uses. The collapsed wall here, still retaining a thickness of around 1.7 metres despite its condition, suggests it was originally a substantial structure, more than a simple field boundary. The double-slab construction visible in the north-west to east section is a detail worth noting; this technique, with an inner and outer facing of slabs, is sometimes seen in enclosures of early medieval date, though without further investigation no firm dating can be offered for Derrysallagh specifically. What is clear is that someone invested considerable effort in building something intended to last, on a hillside in south-west Kerry that looks much as it probably did when the wall was first raised.