This is a cashel, a type of early Irish stone-walled enclosure typically associated with the early medieval period, and the one at Annaglogh is modest but legible, its form preserved beneath the scrub.

When surveyors recorded the site in 1968, it measured roughly 28 metres east to west and just over 26 metres north to south, defined by a stony bank that still stood nearly a metre high on the interior face and slightly more on the exterior. The bank's base was around two metres wide at the north, tapering to half a metre at the top, the kind of proportions that speak to deliberate construction rather than field clearance. Two gaps interrupt the circuit, one at the north-west and one at the south-south-east; the latter, about 1.2 metres wide at the base, is considered the likely original entrance. Adjoining the cashel wall on the west is a rectangular enclosure, open to the south, its other sides formed by earthen and stone banks. Such annexes are not unusual in cashel complexes and may have served as stock pens or working areas associated with whoever occupied the main enclosure. By 2000, the monument had been entirely overtaken by furze, the dense thorny shrub that colonises neglected ground across Ireland with considerable efficiency, leaving the site effectively invisible without clearance.