When excavations by Scally finally brought it back into view, what emerged was a structure that had been substantially altered at some point in its history, leaving behind an asymmetry that speaks to the practical compromises of monastic construction in a difficult landscape.

The enclosure surrounds a church and graveyard on High Island, and its irregular form is the result of two distinct phases of building. The original structure was probably rectangular, but its northern side was later rebuilt further inward, producing a trapezoidal plan measuring roughly nine metres east to west and seven metres north to south, with all four walls running to different lengths. Only the western and northern walls sit in alignment with the church, which has created an uneven corridor of space between the enclosure wall and the church itself, ranging from two metres at the south-west corner to less than a metre at the south-east. The entire interior was paved. Two entrance gaps remain, one to the north-east and one to the north-west. Against the outer face of the eastern wall, a clochan, the drystone corbelled hut common to early Irish monastic sites, was built directly up against the masonry, obscuring it almost entirely. The south-east corner of the same wall has been buttressed. More quietly striking is a cross-slab set into the internal face of the eastern wall near its northern end, its carved surface facing inward into the paved enclosure rather than outward to the sea. The dating of both construction phases remains uncertain, though hearth debris suggests the primary wall was built sometime after the calibrated range of AD 728 to 971.