Allt-fawr

Allt-fawr is a mountain in Snowdonia, North Wales, part of the Moelwynion group. It sits on the edge of Snowdonia National Park and overlooks Blaenau Ffestiniog, a town known for its slate quarries. The mountain also commands views of Llyn Ystradau and Ffestiniog Power Station in Tanygrisiau. Two vast slate mines, Oakeley Quarry and Cwmorthin Quarry, lie on its northern and southern slopes. These mines once connected beneath the summit, and their underground workings have left visible scars on the surface where tunnels have collapsed. The mountain’s industrial past is striking. Oakeley Quarry, the world’s largest underground slate mine, stretches beneath its northern flank. On the southern side, Cwmorthin Quarry is equally imposing. Between 1974 and 1997, Gloddfa Ganol operated as a tourist attraction within Oakeley Quarry, drawing visitors to explore its depths. The scars of these mines remain, with collapsed adits and chambering visible on the slopes. A walk on Allt-fawr offers a mix of natural and industrial scenery. The mountain’s slopes show the marks of centuries of slate extraction, while the wider views stretch over Blaenau Ffestiniog and its quarries. The contrast between the rugged landscape and the remnants of mining work makes the climb memorable. The power station and reservoir below add to the sense of a place shaped by industry. The mountain stands as a reminder of Wales’ slate heritage, its surface a patchwork of old workings and new growth.