It is a raised subcircular platform, roughly nineteen metres east to west and seventeen metres north to south, shaped by a bank along its north-eastern to south-eastern arc and by a natural or cut scarp elsewhere. Running around the whole thing is a shallow, narrow external fosse, the term for a ditch dug to define or defend an enclosed space, and its survival all the way round gives the site an unusual degree of integrity for something so modest in scale.

Enclosures of this type are common across Ireland but rarely straightforward to interpret. They may represent the remains of a ringfort, a farmstead enclosed for protection during the early medieval period, roughly the fifth to the twelfth centuries. They can also be later stock enclosures, or the earthwork traces of a dwelling platform that was raised simply to keep a building above the damp ground. Without excavation it is impossible to say which applies here, and the site at Killallaghtan has not, as far as the available record shows, been dug. What makes this particular example worth noting is its relationship to the nearby graveyard, a spatial proximity that occurs frequently in the Irish countryside and sometimes indicates that a secular enclosure and an ecclesiastical one grew up alongside each other over centuries, each leaving its own mark on the same small patch of ground.