Bethesda, Gwynedd: They make short work of the sardines from my sandwiches. But I don’t begrudge them, for they have a long flight ahead

It’s a bright autumn day as I make my way up by steep paths lined with drystone slate walls through the outskirts of this old quarrying town, making for the high tops of Y Carneddau, the largest land mass over the 3,000ft contour south of the Scottish Cairngorms.

Soon I’m at the fridd wall into the mountain pasture. I wave to some climbing friends at play on the Caseg boulders and set my face to the unremitting grind up the spur of Gyrn Wigau. At its top the gradient eases and I race across to the old path curving in from the north, rounding Drosgl and Bera Bach to head for the summit shelter on Foel Grach.