The most intriguing thing about the fort is that there are ten flights of steps, built in an X shape, along the circular internal wall giving access to the top of the rampart. There are two small rooms, one on the west side of the fort, the other on the south. The stones are skilfully laid, without mortar; the wall, 13 feet thick at the base, rises with a pronounced batter to a maximum height of 18 feet. The south-facing entrance is a 6 feet high passage roofed with massive lintels, the jambs typically converging in the Irish manner. A fosse and ring-bank surround the cashel, adding to its considerable defences.
The technique of dry-walling so well demonstrated here has a long tradition, being found in Neolithic chamber tombs of 5,000 years ago. The survival of so many early structures throughout the Irish countryside is partly due to the mastery of the craft of interlocking stones to achieve total stability, even in large building works like Staigue. The tradition is carried on today on a lesser scale, in the building and maintenance of mile upon mile of field-walls in the rural west.