Somewhere in a broad, flat open field in County Dublin, a circular or near-circular enclosure lies completely buried beneath the surface, leaving no trace visible to anyone walking the ground. The only evidence of its existence comes from the air, where differences in soil moisture and crop growth betray the ghost of an ancient boundary beneath. These crop marks, as they are known, appear when buried ditches or banks cause the plants above them to grow at slightly different rates, creating subtle variations in colour or height that become legible only from altitude, and only under the right conditions.

The site was recorded in the Sites and Monuments Record for County Dublin under the references DU012-076 and DU012-077, the latter designating a second enclosure and an associated field system identified alongside it in the same field. The aerial photograph that revealed these features was brought to wider attention through the work of T. Condit, and the record was compiled by David O'Connor and later updated by Christine Baker. The two enclosures and the field system together suggest a pattern of organised land use from some earlier period, though the notes do not specify a date or culture. Enclosures of this kind, when excavated elsewhere in Ireland, have turned out to belong to a wide range of periods, from the prehistoric to the early medieval.

For anyone curious enough to seek the location out, the site sits towards the western end of what is now described as a vast open field, relatively flat and without obvious landmarks. There are no earthworks, no stones, no visible boundary of any kind. The most a visitor could do is stand in that field and consider what lies beneath ordinary ground, knowing that the record of it exists only because someone once looked down from above at the right moment, in the right season, when the crops happened to be telling the truth.