The Conwy Valley line was constructed as far as Llanrwst in 1863 to the present Llanrwst North station, known originally as Llanrwst and Trefriw in order to cater for the tourist potential of the popular spa village of Trefriw.

In 1868 the line was extended to the famous inland resort of Betws y Coed.

By 1879 the line had again been extended, travelling the 1 in 47 curves up the beautiful Lledr Valley, through the longest single track tunnel in the UK, to arrive in the slate mining town of Blaenau Ffestiniog. The railway provided a valuable means of transporting roofing slates into a rapidly expanding worldwide market at that time.

In addition, other allied industries such as agriculture and forestry benefited from the use of the railway in satisfying the economic needs of the area.