DisgrifiadA semi-subterranean structure with slate walls and capped with slate slabs. Measuring roughly 2m across and 60cm there is a void beneath the slabs. The full extent of the feature is not visible and its function is not evident - possibly a drain culvert? The southernmost slab has two holes in it, both 2cm in diameter. Noted during an upland survey conducted by Archaeophysica during 2005-6