The unusual seven-sided boundary is striking in itself, but what makes the site particularly curious is what it almost certainly conceals: the entirely vanished remains of a medieval parish church dedicated to St Catherine, Virgin and Martyr. By the time Ordnance Survey mappers came through in 1839, and again when the revised edition was produced between 1899 and 1900, no trace of the building appeared on either map. The ground had simply absorbed it.

The ancient parish of Tullamaine, which comprised the townlands of Tullamaine and Knockrea, was united to the Rectory of Callan before 1300, making it a settlement of considerable age. The historian William Carrigan, writing in 1905, described the church as having stood on the sloping ground of Tullamaine where it faces south-west, adding with some finality that every vestige of it had disappeared. The Ordnance Survey Letters of 1839 noted what was then a large and much-frequented burying ground at the site, suggesting that even as the church fabric crumbled away entirely, the community continued to bury its dead here across the centuries. Carrigan also observed that the oldest visible funerary monument in the graveyard dated only to the eighteenth century, meaning that whatever markers once accompanied the medieval burials have long since gone the same way as the church itself.