It takes a particular quality of summer light and a satellite passing overhead to reveal it at all. The enclosure appears as a cropmark, a phenomenon where buried features such as ditches cause the plants growing above them to ripen at a slightly different rate, producing tonal variations that become legible only from the air. On imagery captured in July 2022, the outline of a roughly oval enclosure, approximately 36 metres across on its north-east to south-west axis and around 33 metres on the perpendicular, resolves itself clearly from the surrounding crop.

The enclosure is defined by a fosse, an older term for a defensive or boundary ditch, dug into the earth and long since silted up and buried. This kind of curvilinear enclosure is a common but still poorly understood feature of the Irish landscape, often associated with early medieval settlement, though without excavation it is impossible to assign a firm date or function to any individual example. What makes the Killaloan site particularly interesting is its relationship to a second enclosure of similar character lying roughly 90 metres to the north-north-west. The two were not identified through fieldwork in the conventional sense but spotted and reported by Jean-Charles Caillère through close examination of satellite imagery, a method that has become increasingly valuable in Irish archaeology as freely available platforms like Google Earth improve in resolution and coverage. The proximity of both enclosures to the Suir, roughly 60 metres from the nearest, fits a pattern seen elsewhere in Ireland, where early settlements clustered near river valleys for water, transport, and fertile ground.