The entrance, a lintelled ope set into the inner face of the wall, measures just forty centimetres in each direction, which makes it unambiguous that whatever its purpose, discretion was built into the design from the start.

The site at Doire Na Sagart is a cashel, the Irish term for a ringfort defined by a stone wall rather than an earthen bank. Cashels are found widely across Ireland, most commonly dating from the early medieval period, roughly the sixth to tenth centuries, and typically served as enclosed farmsteads for a single family or small community. This one sits on a south-facing slope in Mid Cork, its roughly circular interior measuring about twenty-two metres north to south and twenty-four metres east to west. The enclosing wall, where it survives, still stands to a height of 1.4 metres and is two metres thick; sections along the north and northeast have collapsed outward. The entrance, two metres wide, faces southeast, a common orientation for sites of this type. Inside, the ground has been deliberately levelled, with the southern edge built up to counteract the natural slope of the hillside, and faint remains of cultivation ridges running north to south hint at domestic agricultural activity within the enclosure. The chamber set within the eastern wall, measuring roughly 1.7 metres by just over a metre, and standing less than a metre high internally, may have served as a small storage space or souterrain-like recess, though its modest scale sets it apart from the larger underground passages, known as souterrains, that are more commonly associated with early medieval settlement sites.