The road passes through a diverse landscape, including the mountainous region of Blaenau Ffestiniog, two estuaries, and the Cambrian Coast.

The road by-passes Glanypwll, Rhiwbryfdir and Tanygrisiau before descending towards the Vale of Ffestiniog along the course of Afon Goedol.

The road passes through the village of Maentwrog, before crossing Afon Prysor near the Ceunant Llennyrch National Nature Reserve.

The road runs alongside the Cambrian Line railway for much of the coast route, bypassing Harlech before ascending inland via the villages of Llanbedr, Llanfair and Dyffryn Ardudwy.

[1] After passing the Barmouth Bridge, the road returns inland, along the northern banks of the Mawddach estuary, via Farchynys and Bontddu.