A rath, the Irish term for a roughly circular earthen enclosure used as a farmstead during the early medieval period, once occupied this gentle prominence. By the 1970s, according to local memory, it had been levelled, reduced to a barely perceptible rise of around 0.3 metres. The ploughed field that replaced it gives little away to anyone walking past.

What makes the site quietly compelling is how stubbornly it refuses to disappear. It was recorded as a hachured circular enclosure on Ordnance Survey six-inch maps in 1842, 1905, and 1935, meaning it survived intact through more than a century of mapping before being lost in a single decade. Its dimensions, roughly 32 metres north to south and 30 metres east to west, place it well within the typical range for a rath of its kind. At the south-south-east edge, a souterrain was recorded, a souterrain being an underground stone-lined passage or chamber associated with early medieval settlement, likely used for storage or refuge. And in aerial photographs, the cropmark of the original bank and its external fosse, the ditch that once ran around the outside of the enclosure, remains clearly legible. More intriguingly still, a second, smaller circular ditched enclosure appears as a cropmark within the interior, concentric to the outer bank, hinting at a more complex arrangement of space than the surface alone would ever suggest.

Cropmarks of this kind appear when buried features affect how crops grow above them, with ditches often producing lusher, taller growth and buried walls the opposite. In dry summers particularly, these differences in vegetation can be striking from the air, revealing whole plans of structures that are otherwise invisible at ground level. At Conva, the earth holds a layout that no longer exists in any physical sense, but which still surfaces, seasonally and obliquely, in the patterns of whatever crop happens to be growing there.