Running in roughly a horseshoe shape, it passes small market towns such as Llanidloes and quiet villages including Abbeycwmhir and Llanbadarn Fynydd, traversing central Mid Wales to Machynlleth near the Dyfi estuary and returning across Wales via Llanbrynmair, Llangadfan and Lake Vyrnwy and the valley of the River Vyrnwy to Welshpool 4 miles from the Wales–England border.