This one, on a west-facing slope in Rahanane, County Kerry, carries an older name that tells a more unsettling story: Lissanaffrin, understood to mean the fort where Mass was said in time of war or the persecution of priests. The name itself is the unusual thing, a piece of local memory preserved in the Ordnance Survey Name Books for the parish of Kilcummin, linking an Early Medieval earthwork to the suppression of Catholic worship in the centuries after the Reformation.

A rath is a type of ringfort defined by an earthen bank rather than stone walls, typically built as a farmstead enclosure during the Early Medieval period, roughly the fifth to twelfth centuries. This example is roughly circular, measuring about 31 metres north to south, with a bank that still stands around 2.6 metres above the outer ground level. An outer fosse, a shallow defensive ditch, remains visible along the south and south-west arc, and there is a possible original entrance about 2 metres wide at the north-east. Within the interior, a raised oval area in the southern half may represent the platform of a former structure. At some point the north-west quadrant of the bank was partially removed, and that space now holds a walled enclosure and a monument commemorating the clandestine Masses said to have taken place here. The practice of celebrating Mass outdoors at informal sites, known as Mass rocks, was widespread during periods when Catholic clergy faced legal penalties, and this rath appears to have served that purpose in local memory, whether or not continuous use can be documented.

The site sits in pasture about 5 metres south of a road, and the earthworks remain clearly legible in the field. The monument in the north-west quadrant is the most immediately visible element, though the bank, the outer ditch, and the raised interior platform reward a slower look around the full circuit.