The enclosure, measuring approximately 40 metres by 25 metres, is not the kind of feature you would easily stumble across on a walk. It took an aerial photograph to reveal it at all, the subtle crop and soil marks reading clearly from above in a way that centuries of farming have rendered nearly invisible from the ground.

The site was identified through the Bruff Survey and catalogued as reference Bruff 142 in aerial photograph AP 4/3658. Doody, writing in 2008, described it as a subcircular ditched enclosure, meaning it would originally have been defined by a dug ditch running around its perimeter, possibly with an accompanying bank of upcast earth. This type of enclosed space, a defined and bounded area set apart from the surrounding landscape, appears widely across prehistoric Ireland. What makes Knockcorragh of particular interest is the shape of the enclosure itself. Doody noted that its morphology, the overall form and proportions of the feature, suggests it may date to the Bronze Age, a period roughly spanning 2500 to 500 BC in Ireland, when such enclosures were used for purposes that could range from settlement and agriculture to ritual activity. No excavation appears to have taken place, so the precise function remains an open question.

Because the enclosure is known primarily from aerial survey rather than fieldwork, there is little visible on the surface for a visitor to find without considerable prior research. The record was compiled by Denis Power and uploaded to the site database in November 2013, drawing on the Bruff Survey mapping. Anyone with a serious interest in the feature would do well to cross-reference the aerial photograph reference before visiting, and to seek landowner permission, as with any site of this kind on private agricultural land. The enclosure is most likely to show as a faint earthwork or as a variation in vegetation, if it shows at all, and patience is required even in conditions, such as dry summers, when crop marks tend to become more legible from an elevated vantage point.