Inside that ring, a small cave-like space was uncovered. Together, these two details suggest the site was once a ringfort with an attached souterrain, though neither feature has survived in any visible form above ground.

A ringfort, sometimes called a rath, was a roughly circular enclosure defined by earthen banks and ditches, used as a farmstead or residence during the early medieval period in Ireland. Many thousands survive across the country, though many others have been levelled by centuries of agriculture, leaving only the faint signature that dark, disturbed soil can provide long after the banks are gone. A souterrain is an underground stone-lined passage or chamber, typically associated with ringforts and thought to have served as storage space, a refuge, or both. The Glannagalt example is documented in J. Cuppage's 1986 archaeological survey of the Corca Dhuibhne region, the Dingle Peninsula, which catalogued a wide range of sites across this archaeologically dense part of County Kerry. The identification rests on local information rather than excavation, and the pairing of a circular soil mark with a subterranean cavity is suggestive rather than confirmed.

What makes Glannagalt quietly interesting is precisely this ambiguity. The site exists now almost entirely as inference, a pattern in ploughed earth pointing to something that may once have stood here, farmed and inhabited, before the land absorbed it back.