The restoration of the Welsh Highland Railway has a colourful and complex history. This article provides the modern history:
The Welsh Highland Railway (WHR) was a poorly funded job creation scheme, conceived in the early 1920s, to complete the construction of a 22-mile narrow gauge railway route from Dinas, three miles from Carnarvon (now Caernarfon) to Portmadoc (now Porthmadog). An earlier scheme to achieve this - the Portmadoc Beddgelert and South Snowdon Railway (PB&SSR) had been abandoned in 1905/6 after it ran out of money.
The Welsh Highland Railway (Light Railway) Company (WHLR) was created in 1922, by a Light Railway Order(LRO), under the Light Railways Act 1896 and construction began that year. The work involved joining two pre-existing railways, with a new section of track. The northern half of the WHR incorporated the North Wales Narrow Gauge Railways(NWGR), built in the 1870s, from Dinas to Rhyd Ddu 91/2 miles, at the foot of Snowdon, together with its branch from Tryfan Junction to Bryngwyn - another three miles. The southern end of the route incorporated an upgraded 3-mile section of the Croesor Tramway, built in the 1860s. Between Rhyd Ddu and Croesor Junction, some new construction on the link between these earlier railways had been carried out by the (PB&SSR) around Beddgelert in 1905/6 but these works lay unfinished.
The PB&SSR section of the route, had originally been intended to use electric traction and would have utilised very steep gradients (1 in 23 in places). However the WHR was to use steam traction and, as steam locomotives could not cope with such steep gradients, only some of the unfinished PB&SSR formation could be incorporated into the WHR. As a result, new formations had to be built, giving rise to the reverse curves above Beddgelert, that gave an even gradient of 1 in 40 (2.5%) over a slightly longer route. At its southern end, the WHR was linked to the Festiniog Railway (FR) at Portmadoc and the FR provided a new station (Portmadoc New) to serve both lines. FR locomotives and rolling stock became a familiar sight on the WHR with through workings.
Construction of the WHR was largely funded by the Ministry of Transport, the local authorities and the construction company McAlpines (who did the construction work). These made loans to the WHLR Company, by taking out debentures - totaling £70,000 and thus the railway was in debt from the moment it opened. The railway was opened throughout in 1923, however his turned out to be the railway's best year; it declined and it went into receivership in 1927.