Gauge: 80cm (2ft 7½ in)
The Snowdon Mountain Railway carries visitors effortlessly to the summit station, 3493 ft (1065m) above sea level. The views that open out during the climb are staggering, from the surrounding mountains to more distant vistas that encompass Anglesey, The Isle of Man and the Wicklow Mountains of Southern Ireland. The gradients of up to 1 in 5.5 are surmountable because this is Britain’s one rack railway. Although rack railways are used elsewhere in the world, notably in Switzerland, this railway provides a uniquely spectacular experience in Britain.
The desire to build a railway up the highest mountain in England and Wales was a favourite ambition of Victorian engineers. After almost fifty years of debate on the possibility, work started in 1894 with the formation of the Snowdon Mountain Tramroad and Hotels Company.
The railway was built, to the Swiss mountain railway gauge of 80cm (2ft 7½ in), on the north western slopes of the mountain from Llanberis, which nestles between the mountains, to the summit station. The rack and pinion system used was patented by the Swiss engineer Dr Roman Abt. The railway uses double rack rails, fastened to steel sleepers between the running rails. Each locomotive is equipped with toothed pinions (cogwheels), which engage the rack and provide all the traction necessary to scale the steepest inclines. On the way down, the rack and pinion system acts as a brake.
Construction was rapid and the first passenger train ran on April 6 1896. Sadly the day was marred by the railway’s only fatal accident following a locomotive derailment. Ironically the unfortunate victim jumped off the train. All the passengers who kept their seats were uninjured. This accident resulted in closure while the entire line was fitted with a modification to the rack system. Since the reopening in April 1897 there have been no further serious accidents.
The total length of the railway is 4 miles 1188 yards (7.53 km). The single track line has passing places at Hebron, Halfway and Clogwyn stations allowing several trains on the line at once. The powerful locomotives haul themselves up the mountain, pushing their single coach at five miles an hour. Higher speeds are unnecessary on such a railway. The coach is not coupled to the locomotive, but simply rests against it on the slope. This is a precaution should the locomotive leave the track. The steam locomotives were built in Switzerland at the Swiss Locomotive and Machine Works. Their boilers are inclined to ensure that the boiler tubes and firebox remain submerged when on the gradient, a standard practice on mountain railways.
Between 1986 and 1992 the company purchased four British built diesel locomotives to complement the steam fleet. These locomotives are powered by six cylinder turbocharged Rolls Royce diesel engines and were built by the Hunslet Engine Company.
In 1995 the railway acquired three diesel-electric railcars. Each unit is capable of being coupled with one or two other units for operation under the control of a single driver and guard. They brought modern technology to the railway with their computer controlled electric transmission system.
1 Ladas Schweizerische Lokomotiv und Maschinenfabrik No 923 of 1895; destroyed in accident
2 Enid Schweizerische Lokomotiv und Maschinenfabrik No. 924 of 1895.
3 Wyddfa Schweizerische Lokomotiv und Maschinenfabrik No. 925 of 1895.
4 Snowdon Schweizerische Lokomotiv und Maschinenfabrik No. 988 of 1896.
5 Moel Siabod Schweizerische Lokomotiv und Maschinenfabrik No. 989 of 1896.
6 Padarn Schweizerische Lokomotiv und Maschinenfabrik No. 2838 of 1922.
7 Ralph Schweizerische Lokomotiv und Maschinenfabrik No. 2869 of 1923.
8 Eryri Schweizerische Lokomotiv und Maschinenfabrik No. 2870 of 1923.
9 Ninian Hunslet Engine Company Diesel Loco No. 9249 of 1986.
10 Yeti Hunslet Engine Company Diesel Loco No. 9250 of 1986.
11 Peris Hunslet Engine Company Diesel Loco No. 9305 of 1991.
12 George Hunslet Engine Company Diesel Loco No. 9312 of 1992.
21 HPE Tredgar Ltd Diesel Electric Unit No. 1074 of 1995.
22 HPE Tredgar Ltd Diesel Electric Unit No. 1075 of 1995.
23 HPE Tredgar Ltd Diesel Electric Unit No. 1076 of 1995.