Look from the air, however, and the soil tells a different story. A circular enclosure roughly thirty metres in diameter reveals itself as a cropmark, the kind of ghost-image that appears in aerial photography when buried features such as a fosse (a defensive or boundary ditch) affect how crops grow above them. Where soil fills an ancient ditch, vegetation tends to grow taller and greener; where buried stone or compacted ground lies close to the surface, it tends to be sparser. The result, visible from altitude in the right season and light, is a faint but legible outline of something that was once deliberately constructed.

The enclosure at Annamult was identified on an aerial photograph taken on 16 July 1971, part of the Cambridge University Collection of Aerial Photography. What makes the site particularly striking is that it does not sit in isolation. Three further enclosures are visible in the same photograph within the immediate vicinity, one lying roughly forty metres to the north, another about a hundred and ten metres to the north, and a third approximately a hundred and thirty metres to the east. Clusters of enclosures like this are known elsewhere in Ireland and are generally associated with early medieval settlement patterns, where a principal ringfort, a roughly circular earthwork used as a farmstead or dwelling, might be accompanied by satellite enclosures serving agricultural or ancillary purposes. The enclosure itself has been partially cut through by a later field boundary running roughly east to west across its northern portion, a reminder that the landscape continued to be divided and reorganised long after whatever originally stood here fell out of use.