It came to light not through any deliberate search but through an aerial photograph taken in July 1989, when crop stress revealed the shadow of a fosse, the defensive or boundary ditch that once defined the enclosure's southern half, etched into the earth below.

What followed was more than a decade later when researcher Doody investigated the site in 1995 as part of the Discovery Programme's Ballyhoura Hills Project, a landscape-scale research effort examining the archaeology of the Ballyhoura Hills region. Two sections were cut through the fosse, one to the west and one to the south-east, and the two proved to be quite different from each other. The western section showed a steep-sided, broadly U-shaped ditch, around 2.18 metres wide at the top and tapering to 0.6 metres at its flat base, filled largely by natural silting with some possible domestic refuse mixed in. Finds included iron slag, an unfinished perforated stone, and an iron bolt. The south-eastern section was asymmetrical, more steeply cut on its north-western side, and its fill told a different story: furnace bottoms, iron slag, and burnt animal bone pointed clearly to the dumping of industrial and domestic waste. The fosse, a term simply meaning a ditch dug as part of a boundary or defensive feature, also appears to have been cut through the already-levelled bank of an earlier, slightly irregular enclosure on the same ground, suggesting this corner of Conva was used and reworked across more than one period of activity. Radiocarbon dating was attempted but returned inconclusive results, leaving the precise chronology open. Two associated pits added further complexity: one to the west had been partially cut through by the fosse itself, while another to the south-east sat just inside its inner edge.

The enclosure belongs to a small cluster of related features at Conva, including two further enclosures and additional pit deposits, all of which together hint at a place that saw sustained, if intermittent, human activity. The iron-working residues and burnt bone recovered from the ditch fill are modest fragments, but they carry the trace of people working metal and processing food somewhere nearby, their refuse eventually tipped into a boundary ditch that was already falling out of use.