It was visible, just barely, in an aerial photograph taken in 1970, a rectangular outline set into low-lying marshy ground at Baldoyle. Three years later it was gone, or at least covered, when the Seagrange housing estate was built across the site in 1973. What the diggers and foundations did not destroy, the soil may still preserve.

The site was first recorded from a Cambridge University Collection of Aerial Photography image, reference AIG 95, which captured the enclosure from the air before development swallowed it. The feature has been interpreted as a possible moated site, a term referring to a class of medieval monument common in lowland Ireland, typically comprising a raised platform or building surrounded by a water-filled ditch, often associated with Anglo-Norman settlement in the twelfth and thirteenth centuries. The marshy character of the original ground would have made such a water management system both practical and relatively easy to construct. Whether any substantial archaeology survives beneath the estate is still an open question. The Grassroots Archaeology project, a community-led initiative working in partnership with local residents, has spent two seasons attempting to find out. Geophysical survey of the open space within the estate, carried out under licence 13R026, identified a natural spring and an anomaly that may represent a leat, a channel used to direct water. Test-excavation under licence 13E0238 has not yet uncovered the enclosure ditch itself, but medieval pottery has come out of the ground, confirming that human activity of the right period took place here.

The Seagrange estate sits in Baldoyle, on the northside of Dublin Bay, and the open green spaces within it are where the survey and excavation work has been focused. The archaeology here is not visible on the surface, and there is nothing to see in the conventional sense. What makes the site worth knowing about is the method: a community project quietly working through back gardens and patches of grass, recovering fragments of the medieval world from beneath a mid-twentieth-century housing scheme. Anyone with a particular interest in this work would do well to look into the Grassroots Archaeology project directly, as the excavation and survey findings continue to develop.