It is described in the Caernarvonshire Inventory, Vol. II, 170 (1144). Huts in Cwm Dwythwch. A small long hut and two sub-rectangular structures, on the mountain slopes W of Llyn Dwythwch, may be the remains of hafodau mentioned in 1352. (iii) Small squarish building on the steep open hillside at 1200ft above OD. It measures 18ft 3ins by 14ft 3ins with a doorway in one of the lower corners. The dry-built walls incorporate an immense natural boulder in one side. Condition: poor. OAN Site visit 2007. The site is a small sub-square shelter with an earthfast boulder on the northern end. It is shown on the current OS mapping and measures 7m long by 6m wide and is mostly collapsed.