This circular earthwork, measuring approximately 5 metres across its interior, consists of a fosse (or ditch) that runs around the perimeter, roughly 2.7 metres wide and 0.3 metres deep. The earthen bank that once encircled the entire structure now survives only on the northern and western sides, where it rises to a height of about 35 centimetres above the surrounding ground.

Ring barrows like this one were typically constructed during the Bronze Age, though some date to the Iron Age, and served as burial monuments for individuals of some standing in their communities. The circular ditch would have been dug out and the excavated soil piled up to form the surrounding bank, creating a defined ritual space. While many ring barrows elsewhere in Ireland and Britain have yielded cremated remains and grave goods when excavated, the Knocknashangan example remains uninvestigated beneath its covering of dense vegetation.

The site’s location is particularly noteworthy, as Bronze Age communities often chose prominent positions in the landscape for their burial monuments, even if only slightly elevated above the surrounding terrain. The marshy ground that now characterises the area may have been drier when the barrow was constructed, or perhaps the wet conditions were deliberately chosen for their liminal qualities; places between land and water were often seen as sacred boundaries between worlds in prehistoric belief systems. Today, nature has largely reclaimed the monument, with thick overgrowth obscuring much of its form, yet its presence continues to mark this quiet corner of Donegal as a place where ancient peoples once gathered to honour their dead.