It measures approximately 35 metres north to south and 32 metres east to west, and while it is still clearly defined by its enclosing bank, several breaches cut through that bank, most of them apparently the work of relatively recent hands rather than centuries of slow decay.

This is a rath, the Irish term for a ringfort, the most common monument type surviving in the Irish countryside. Ringforts were typically enclosed farmsteads of the early medieval period, roughly the fifth to twelfth centuries, used by a single family or small farming community. The enclosing bank, sometimes accompanied by a ditch, defined a boundary that was at once practical and social, marking out a household's space within the landscape. Thousands survive across Ireland in varying degrees of completeness, though many have been levelled by agriculture over the past two centuries. The one at Cloonrane has fared better than most, its position on raised ground amid bogland offering a degree of natural protection, the surrounding terrain being less suited to the plough than to the grazing that still characterises it today.