It measures roughly nine metres by five, defined by a low drystone wall, and it holds the remains of children who, for reasons rooted in centuries of Catholic practice, could not be buried in consecrated ground. These sites, known in Irish as cillíní, were the quiet solution to a painful problem: unbaptised infants, and sometimes others considered marginal to the formal Church, were interred in places set apart, often at liminal locations such as old ringfort boundaries, cliff edges, or, as here, the shoulder of a ridge overlooking open farmland.

The enclosure at Blean is subrectangular in shape, a form common to these sites, and its boundary wall is built in the drystone tradition, meaning no mortar, just carefully selected and stacked stone. Only a single headstone is visible, positioned at the western end. Three yew trees grow within the interior. Yews are a recurring presence in Irish burial grounds of all kinds; long-lived and evergreen, they accumulated associations with death and continuity long before Christianity arrived, and those associations proved durable. Whether planted deliberately or self-seeded over generations, their presence at Blean gives the site a quality that is quietly monumental, disproportionate to its modest dimensions.

Cillíní were used well into the twentieth century in many parts of Ireland, and their study has grown considerably in recent decades as historians and archaeologists have worked to document sites that were largely absent from official records. Many were known only within local memory, their locations passed down without formal acknowledgement. The single visible headstone at Blean hints at a community that, at some point, chose to mark at least one grave more formally, even within a space that the wider Church did not recognise.