The site measures roughly 17.8 metres by 13.5 metres, bounded by a substantial drystone wall three metres wide and faced on both sides, with a narrow entrance of just 1.2 metres set at the north-north-east. Inside, a roofless subrectangular clochan, the term for a corbelled dry-stone hut of early medieval type, occupies the western half of the interior. Traces of what may be a second clochan, now almost entirely gone, survive in the eastern half. It is the sort of place that seems straightforward until you look more carefully.

The enclosure is traditionally associated with St Leo, a dedication noted by O'Flanagan as far back as 1927, and Kinahan recorded the site in 1869. Early ecclesiastical enclosures of this kind were commonly built to define sacred space around a church, hermitage, or monastic cell, and the association with a named saint places Cloghanleo within a recognisable pattern of early Irish Christianity. What complicates the picture is a detail uncovered during detailed planning and survey work published by Kuijt and colleagues in 2010: a line of five head or footstones, set in the ground to the north of the possible second clochan. These may be contemporary with the original enclosure, but they may equally point to a later, secondary use of the site as a burial ground. The suggestion that the burials could be those of children adds a particular weight to the question. Whether the stones mark the earliest phase of the site's use or a community's quiet recourse to an already sanctioned space in harder times is not yet resolved.

Inishshark was permanently evacuated in 1960, when its remaining inhabitants were resettled on the mainland, so the island is now accessible only by arrangement with boat operators from the nearby village of Cleggan. The enclosure lies close to the south-eastern shore, on exposed rock, and the site's position means the drystone walling and the low stones inside are the main things to look for, undramatic in themselves but clearer once you know what the outline signifies.