Harlech clings to a rugged cliff edge where the mountains of Eryri meet the sweep of Tremadog Bay. The town is crowned by its medieval castle, a dark stone fortress that has stood against sieges and storms for centuries. My top tip is to climb the steep stone steps of Ffordd Pen Llech, once noted as one of the sharpest hills in the world. You can walk the miles of wild dunes and golden sand at the beach for free. The scent of salt air and pine needles drifts from the nearby woods. Local galleries sell craft goods made from Welsh slate. Life here is slow and feels shaped by the ancient myths of the Mabinogion. It is a grand spot for a walking holiday under the high peaks.