On a small hillock in County Waterford, a single ogham stone survives where three once stood. Ogham is an early medieval script, typically carved as a series of notches and lines along the edge of a stone, and used mainly in Ireland between roughly the fourth and seventh centuries to record names and mark territory or burial sites. That one stone remains at Seemochuda at all is partly a matter of luck and partly a matter of function: it was incorporated into a structure known as a Saint's chair, a stone seat associated with early Christian veneration, which offered it some degree of protection.

Writing in the Journal of the Waterford Archaeological Society in 1899, a researcher named Power recorded local accounts that the hillock originally held three stones. The surviving example formed the back of the Saint's chair and has since been removed to University College Cork for safekeeping. The other two stones, which may also have carried ogham inscriptions, were not so fortunate. According to those same local accounts, they were rolled down the slope of the hillock into the stream to the west at some point before Power's documentation. Neither stone has been identified or recovered, and what inscriptions they might have carried, what names or formulas they preserved, remains unknown.