A cashel is a stone-walled enclosure, typically of early medieval date, and this one sits on a natural limestone terrace running roughly east to west in an area of karstic outcrops and rough pasture. The site is defined not by a standing wall but by a scarped platform, essentially a cut or shaped edge to the terrace, rising between half a metre and a metre. Whether the low line of stones running along the base of the northern scarp represents the remnant of a deliberate limestone revetment, a facing built to stabilise or reinforce the edge, or simply a natural arrangement of rock, remains unresolved. That ambiguity is unusual. Most recorded cashels have at least some clearly worked stonework to anchor the identification.

The site appears on the 1842 Ordnance Survey six-inch map and again on the 1920 edition, where it is named Cahermacrusheen. Tim Robinson's 1977 map of the Burren gives the Irish form, Cathair Mhic Croisín, meaning roughly the stone fort of the Mac Croisín family. Inside the roughly subcircular enclosure, which measures approximately 40 metres east to west and 35.5 metres north to south, the ground slopes gently southward and is thick with thistles and nettles. Beneath that growth, very low earth and stone banks hint at internal divisions or structures, though their precise nature is unclear. Two short stretches of a collapsed grassed-over bank survive near the northern and eastern edges and are thought to be what remains of the enclosing wall. The cashel also sits within a larger multiperiod field system, suggesting the landscape around it was organised and reorganised across a long span of time. A modern water trough and farm shed, built against the southern scarp, complete the layered picture of a place that has been in continuous, if shifting, use.