Catalogued provisionally as a ringfort, or rath, the site presents a raised, slightly domed area some 44 metres in diameter, defined by a low scarp between 0.8 and 1.1 metres in height. A rath is typically an early medieval enclosed farmstead, its boundary bank marking off a domestic space from the surrounding land. This one, however, carries an asterisk: surveyors have noted that it may be a landscape feature rather than a genuine antiquity, meaning the earthwork could be a deliberate ornamental or agricultural shaping of the ground rather than the remnant of early settlement.

That ambiguity is, in its own way, telling. The demesne context matters here. Demesne lands, the home farm and ornamental grounds attached to a country house, were frequently reshaped during the eighteenth and nineteenth centuries to satisfy aesthetic fashions. Circular mounds, serpentine paths, and carefully graded scarps were all tools of the designed landscape. Whether this particular raised circle was always part of the land's natural roll, was sculpted by hand at some point during Tanrego House's history, or is genuinely the eroded remains of a much older enclosed settlement, nobody has yet been able to say with confidence. The planting of coniferous trees across the domed interior adds another layer of alteration, further complicating any reading of the ground beneath.