A line of anti-tank blocks was noted near the head of Happy Valley (Cwm Maethlon), below Llyn Barfog. They form a straight line of spaced blocks, at right angles to the unclassified valley road (Cwrt - Towyn), four on each side. They lie at a point on the road where the pass narrows, making use of rock outcrop on the north side and a tributary stream on the south. The overall length of the line is some 25m.
The simple alignment of the blocks, with adjacent sides parallel to each other, points to a 1939-40 date for their construction.
David Leighton, RCAHMW, 28 June 2011
Surviving Anti-invasion defences (anti-tank cubes) around Fairbourne and Cader Idris: part of Western Command Stop Line No.21
