The enclosure at Ranagissaun sits straddling a gentle ridge, and what makes it quietly odd is the way it has been held together by two entirely different means: its western half defined by a sod-covered bank of earth and stone, its eastern half by a drystone field wall, the kind of uncemented dry-laid construction that has been used in the west of Ireland for millennia. The two halves form a single oval roughly 21 metres north to south and 15.5 metres east to west, but they read differently on the ground, as though the structure was repaired, reused, or simply altered at some point in its life.

The western bank is the more archaeologically interesting of the two. Its outer face, particularly at the south-west, is roughly dressed with upright slabs and occasional boulders, suggesting some care was taken in its original construction. More intriguing is the band of markedly wet ground, roughly two metres wide, running immediately outside this bank. This may represent the remnant of a fosse, the term for a defensive or boundary ditch associated with enclosed settlements, though it is absent on the eastern side, which complicates any straightforward reading. A faint undulation detected three to four metres beyond the eastern field wall may mark where the enclosure originally extended before the later wall was built. Inside, the ground is slightly raised at the north-east and falls gently toward the south and south-west, with a shallow hollow sitting against the inner face of the stone bank at the north-east. A gap of about 2.4 metres at the west-north-west likely marks an original entrance. The interior is now planted with conifers, which obscure the surface detail but have probably also protected it from heavier agricultural disturbance.

Two streams flank the site, one about 40 metres to the south-west and a larger one roughly 70 metres to the east, a pattern of water proximity common to enclosed rural sites across Ireland, where drainage and water access both mattered. The enclosure offers good views from its low rise, suggesting its position was chosen with some awareness of the surrounding landscape.