A4212 (Great Britain)
The A4212 is a 17 mile road between Bala (Y Bala) and Trawsfynydd in North Wales, by way of a 401m (1316 ft.) summit at Llyn Tryweryn. There are many straight sections on this road and only one short 40mph speed limit at Frongoch.
History
The road was created in the early 1960s or, by improving existing B roads and new construction in Cwm Prysor and around the Llyn Celyn, replacing the Bala and Festiniog Railway that was closed to passengers in 1960 (1961 for freight). The route improved access for the construction of both Llyn Celyn and the Trawsfynydd nuclear power station. It also provided a new and useful east-west link south of the A5 and, with routes east of Bala, via Llangynog, to Nesscliffe (Wolf's Head roundabout) on the A5, an important holiday route from the Midlands to the North Wales Coast at Porthmadog and Harlech. The route uses two high mountain passes: the Milltir Cerrig between Llangynog and Bala, and this pass between Bala and Trawsfynydd.