Уэльстің ең ұзын жолы: Кардиффтен Гланконуиге қарай A470 трассасы

Major long distance road in Wales

The A470 (also named the Cardiff to Glan Conwy Trunk Road) is a trunk road in Wales. It is the country's longest road at 186 mile (299 km) and links the capital Cardiff on the south coast to Llandudno on the north coast. While previously one had to navigate the narrow roads of Llanidloes and Dolgellau, both these market towns are now bypassed due to extensive road modernisation. The 26 mile (42 km) from Cardiff Bay to Merthyr Tydfil are mainly dual carriageway, but most of the route from north of Merthyr to Llandudno is single carriageway.

The road travels through two of the national parks of Wales: the Brecon Beacons, and Snowdonia National Park starting just south of Dinas Mawddwy.

The southernmost point of the route is in Cardiff Bay, outside the Wales Millennium Centre. It runs up Lloyd George Avenue (this was previously Collingdon Road, and the A470 previously ran along the parallel Bute Street), and continues along St. Mary Street in central Cardiff. The road then becomes North Road, and after a tidal flow system running to Maindy and then goes over the flyover at the Gabalfa interchange of the A48 and the A469. It becomes an urban dual carriageway along Manor Way, with a speed limit and with many traffic signalled crossings. It passes without interruption under the M4 at the giant Coryton roundabout. For the next 15 mile (24 km) it is a modern high speed dual carriageway by passing Tongwynlais and Castell Coch, Taff's Well, to Pontypridd. Heading north to Abercynon, the road now follows the route of the Taff Vale Railways Llancaiach Branch to Quakers Yard roundabout, where it is joined by the A4059 from Abercynon, Aberdare and Hirwaun ; the A472 from Ystrad Mynach and Pontypool finally the A4054 from Quakers Yard, and Merthyr Tydfil. From Quakers Yard roundabout (locally known as "Fiddlers Elbow"), 5.5 mile (9 km) of dual carriageway takes the road to the Pentrebach roundabout where the A4060 links, and then to the Merthyr Tydfil roundabout where the road meets the A465 and the dual carriageway ends. A twisting section alongside the Taf Fawr reservoirs of Llwyn on, Cantref and Beacons takes the road to its highest point at Storey Arms on the pass over the Brecon Beacons before a long descent to Brecon.

The remainder of the route north of Brecon consists of older routes now renamed "A470". This artificiality is apparent as a driver following the entire route north to south must diverge from the main line of respective stretches of road no fewer than five times. A short three lane stretch heads north east before a sharp left turn is required to stay on the road. From this point on the road becomes narrow and twisting and overtaking is problematic except at a few straight sections. Another sharp left turn at a stop sign in Llyswen takes the road alongside the River Wye into Builth Wells.

The road continues to follow the Wye to the busy crossroads where it meets the A44 in the centre of Rhayader. On reaching Llangurig, a right turn outside the village takes the road past Llanidloes and through Llandinam, the birthplace of David Davies and now the headquarters of Girl Guides Wales. Another anomalous left turn at a level crossing sets the path for Caersws, Carno and Llanbrynmair. Just beyond the village of Talerddig the road descends and crosses under the Shrewsbury–Aberystwyth railway line. The long descent towards Commins Coch is a relatively new stretch of road that replaced a set of road works that had traffic light controlled single lane working for over 10 years because of unstable ground conditions. The river bridge at Commins Coch is so narrow and set at such an angle that only one vehicle at a time can pass. At Cemmaes Road the road joins the A487 at a roundabout. A right turn at the roundabout takes the road on to Mallwyd where the A458 joins at yet another roundabout.

The country becomes more forested and the road climbs up through Dinas Mawddwy and then steeply up the eastern foot hills of Cadair Idris before dropping down to the Dolgellau by pass. More sharp twists and turns in the forestry and through the village of Ganllwyd brings the road up onto the high plateau of the Cambrian dome where the road follows the ancient track of Sarn Helen Roman road passing the redundant nuclear power station at Trawsfynydd. A right turn beyond the power station takes the road on to Ffestiniog and Blaenau Ffestiniog before heading over the Crimea Pass to Dolwyddelan. A sharp left turn interrupts the A470 as it becomes the A5 for a short distance towards Betws y Coed before turning right again back onto the A470 just before Waterloo Bridge. Passing down the valley of the River Conwy the road passes through Llanrwst, Tal y Cafn and Glan Conwy, at which point there is a dual roundabout that intersects with the A55 North Wales Expressway before descending into Llandudno. The northernmost point of the route is in Llandudno itself at the sea front, where it meets the North Shore Parade, the A547.