This site is believed to mark the location of Desertegny, an early ecclesiastical foundation that scholars Gwynn and Hadcock documented in their 1970 survey. The graveyard’s curved wall, which sweeps from east to south, likely follows the footprint of a much older religious enclosure, suggesting this sacred ground has been in continuous use for over a millennium.

At the heart of the graveyard stand the ruins of a Roman Catholic church, its stone walls oriented northwest to southeast rather than the traditional east-west alignment. Built sometime during the 18th or 19th century, this church represents just one layer of the site’s long religious history. The graveyard itself serves as an open-air museum of early Christian stonework, with numerous crude stone crosses and cross-inscribed stones scattered throughout the grounds, each one a testament to centuries of faith and craftsmanship.

Perhaps the most intriguing monument lies northwest of the church ruins: a cross-shaped stone bearing a cupmark on each of its faces. These cup-shaped depressions, carved deliberately into the stone, connect this Christian site to much older traditions; cupmarks appear throughout Ireland and Britain on monuments dating back to the Bronze Age. Whether these marks were carved when the cross was first erected or added to an existing prehistoric stone that was later Christianised remains a mystery, but their presence adds another fascinating layer to Greenhill’s already rich archaeological story.