A bullaun stone, one of those enigmatic boulders bearing one or more cup-shaped depressions ground into their surface, once sat here. Bullauns are found throughout Ireland, often near early medieval ecclesiastical sites, and their hollows are thought to have served ritual, grinding, or votive purposes, though no single explanation has ever fully satisfied scholars. This particular stone has since been removed.

The stone was relocated to the grounds of Glendalough House, a short distance away in the same county. What remains at Ashtown is, in a sense, an absence, a site defined now by what was taken rather than what stands. The act of moving a bullaun was not unusual in the post-medieval period, when landowners occasionally gathered ancient stonework as curiosities or garden features, displacing objects from the field contexts that gave them meaning. Whether that is what happened here is not recorded, but the pattern is familiar enough across the Irish landscape.