Others exist only as a faint discolouration in a crop, visible for a few days each summer when the right drought stresses the soil above a buried ditch. The ring-ditch at Ballynamona in north Cork belongs to this second, more elusive category. What the eye can make out, from the air at least, is a roughly circular fosse, or ditch, around ten metres in diameter, its outline pressed into the field below like a watermark held up to light.

The feature was captured in an aerial photograph taken in July 1989 as part of a systematic survey of Cork's archaeological landscape. A fosse of this kind, encircling a space barely the width of a large room, is generally interpreted as the remnant of a ring-ditch, a class of monument often associated with prehistoric burial or ritual use, where a circular trench once defined a sacred or ceremonial boundary. What makes Ballynamona particularly interesting is the company it keeps. A ringfort, the remains of an enclosed farmstead of the early medieval period, lies roughly a hundred metres to the north, and a second circular enclosure sits about forty metres to the west-southwest. Linear cropmarks in the same field may trace the ghostly outlines of old field boundaries, suggesting that this patch of ground has been organised, farmed, and marked out by people across a very long stretch of time. Whether the ring-ditch and its neighbours form a meaningful spatial cluster or simply reflect the way past communities repeatedly chose the same tractable ground is a question the surface cannot answer.