The rath at Kiltullagh is a subcircular earthwork, measuring roughly 50 metres north to south and 37 metres east to west, and although it is heavily overgrown it retains a legible profile. A rath is an early medieval enclosed farmstead, typically dating from somewhere between the fifth and twelfth centuries, built by digging a circular ditch and throwing the spoil outward to form a bank. Here, that basic grammar is still readable: an inner scarp rising to nearly two metres, a fosse, which is the ditch between the inner and outer earthworks, running two and a half to three metres wide, and an outer bank that stands over a metre high on its inner face.

What makes this particular example quietly interesting is the way later land use has left its own marks on the earlier structure. Along the arc from the north-east around to the south-south-east, a field bank has been built directly on top of the outer bank of the rath, folding the ancient boundary into the more recent business of dividing agricultural land. It is a small detail, but it tells you something about how long this landscape has been managed and subdivided. The rath was not demolished or ploughed out; it was simply absorbed into a newer pattern of enclosure, its earthworks too substantial to remove and too useful to ignore. Roughly twenty metres to the north-east, a holy well, a site type associated in Ireland with pre-Christian and early Christian veneration alike, sits close enough to suggest the two features share a long relationship in the local geography of this townland.