Corn-barn at Trefarthen (N side of yard)

The corn barn at Trefarthen is a five-bay structure dating from the 19th century. It features wide opposed doors at the center and a granary loft at one end, which is accessed by external stone steps at the rear. The walls are made of coursed rubble and include two tiers of slit vents on the lateral walls, with five vents to the left (west) of the door and two to the right (east). The gable walls also have three levels of slit vents. The barn has a pitched slate roof with slate slab copings. The central tall doors are topped with a stone voussoir basket arch, and there are blocked openings to the right (east). The granary loft on the east side has two modern windows in the lateral wall and two windows with ventilators in the gable wall. Inside, the granary features a king-post roof truss, with '1829' painted on the tie-beam.