These burial grounds, known in Irish as cillíní, were used for centuries to inter infants who died before baptism, along with others considered ineligible for consecrated ground. Excluded from the parish churchyard by Church teaching, such children were quietly buried at liminal places, field boundaries, old ringfort interiors, or slopes overlooking water, in grounds that existed outside the formal structures of religious authority.

The Annaghkeen site covers a roughly rectangular area measuring approximately twenty metres east to west and just under seventeen metres north to south, defined by a scarp rather than a built wall. Inside, numerous small stones are set into the ground, each one oriented east to west in keeping with the tradition of Christian burial, despite the site's unofficial character. What makes the layout particularly striking is a concentration of taller grave-markers gathered in the north-east corner, suggesting either a later period of use or simply that some families had more means than others to mark where their children lay. The site was noted in O'Flanagan's 1927 survey and recorded again in the published Archaeological Inventory of North Galway, compiled by Olive Alcock, Kathy de hÓra, and Paul Gosling.

The slope above the lough would have made the location easy to identify for families approaching in grief, and the view across Corrib remains the same today. The stones themselves are modest, uncut for the most part, and easy to overlook without knowing what they signify.