During the Second World War, the War Office used the Preseli Hills extensively for training exercises by British and American air and ground forces. Its proposed continued use after the war was the subject of a two-year ultimately successful protest by local leaders. The success of the protest was commemorated 60 years on, in 2009, with a plaque at each end of the Golden Road: one at the foot of Foel Drygarn near Mynachlog-ddu, and the other near the B4329 at Bwlch y Gwynt.