|Length:||32 mi (51 km)|
| A470 road
The road passes through Pennal, Aberdyfi, Tywyn, Bryncrug, Llanfendigaid, Rhoslefain, Llangelynin, Llwyngwril, Friog, Fairbourne, Arthog and Penmaenpool. The road is approximately 32 miles long. Because of the location of the road which is next to the coast for the majority of the journey, road surveying is essential to prevent landslips into the sea. Retaining walls are often used and stone walls are used instead of safety rails to help conservation efforts in Snowdonia National Park.
- A Vauxhall advertisement was filmed at Penmaenpool toll bridge and the scenes were shot from the A493 road.