Caherfarreesh, known in Irish as Cathair Fearghais, a cashel or stone-walled ringfort sitting on a slight rise above Ballinskelligs Bay on the Iveragh Peninsula, is one of those sites where the continuity of agricultural life has both preserved and obscured something considerably older. A cashel is essentially a ringfort built from stone rather than earthen banks, a form common across the west and south-west of Ireland, typically dating from the early medieval period. Here, the modern field boundary that crowns the wall traces the same irregular outline the fort had when it was first mapped on the nineteenth-century Ordnance Survey, which suggests the old enclosure has been quietly directing the movement of livestock and the logic of land division for well over a century.

Beneath that later boundary, the original wall can still be followed along the western half of the circuit, where large boulder-like slabs face both the inner and outer surfaces of a rubble core roughly three metres wide. The eastern side preserves the original entrance, just over a metre across, with an upright slab standing a metre high on its southern flank, the kind of threshold marker that would have given the entrance a funnelled, deliberate quality. The interior, which measures roughly 24.7 metres north to south and 21.8 metres east to west, is taken up in large part by a rectangular structure, 8 metres by 11 metres, whose walls survive to about 70 centimetres. This later building, sitting inside the ancient enclosure, is considered to be of no great age, a reminder that a defensible stone ring was often put back to use long after its original purpose had faded.