No ridge, no shadow, no irregularity in the soil gives it away at ground level. Its existence is known almost entirely from a single aerial photograph taken on 16 July 1971, part of the Cambridge University Collection of Aerial Photography (reference CUCAP BGG060), in which the buried boundaries of a co-axial field system became legible from above in a way they never could from below.

A co-axial field system is one of the more methodical expressions of early land organisation: a series of roughly parallel boundaries, sometimes running for considerable distances, with smaller dividing lines crossing them at intervals, the whole arrangement oriented along a common axis. Here, that axis runs roughly north-east to south-west across the valley floor. What makes the Connahy system particularly interesting is its possible relationship to two ring-ditches also recorded within the same area. Ring-ditches are typically the ploughed-down remains of prehistoric burial mounds or ceremonial enclosures, their original earthworks long since levelled, surviving only as circular crop-mark anomalies visible from the air. If the field boundaries and the ring-ditches are genuinely related, it would suggest that whoever laid out this landscape was doing so in deliberate proximity to earlier monuments, a pattern recognised at prehistoric field systems elsewhere in Ireland and Britain. Whether that relationship is functional, symbolic, or simply a coincidence of survival is not yet clear.