The earthwork that once marked its location, a rath or enclosed ringfort of the kind built across Ireland during the early medieval period, has been so thoroughly flattened by centuries of agricultural activity that little visible trace remains above ground. Yet local knowledge holds that the souterrain survives intact beneath the surface.

A souterrain is a man-made underground structure, typically constructed from dry-stone walling and roofed with large capstones, that was built in association with early medieval settlements in Ireland. They served various purposes, most likely as cool storage for dairy produce, as places of refuge, or both. The rath at Lissaniska, recorded as MA092-067, would have been a roughly circular earthen enclosure of the type that once defined a farmstead or small settlement, probably dating to somewhere between the sixth and twelfth centuries. That the enclosing bank and ditch have since been levelled is not unusual; thousands of raths across Ireland were removed during land improvements, particularly in the eighteenth and nineteenth centuries, though their subterranean features often endured long after the surface structures disappeared. In this case, local tradition preserves the knowledge that something remains below.