Snowdon Mountain Railway
The Snowdon Mountain Railway (Welsh: Rheilffordd yr Wyddfa) is a narrow gauge rack and pinion mountain railway in Wales. The line is a tourist railway that travels for 7.5 km (5 miles) to the summit of Snowdon, the highest peak in Wales. It is the only public rack railway in the British Isles and after more than a hundred years of service, it remains a highly popular tourist attraction. It is operated by both steam and diesel locomotives.
The route and operation of the railway
The railway starts at the side of the main road in Llanberis and consists of a single track with passing loops spaced along its length between Llanberis and the summit. The spacing of the loops is such that they are around 15 minutes travelling time apart. All three passing loops are on the North-west side of the line so that, if traffic was heavy, the line could easily be converted to double track.
The total length of the railway is 4 miles 1188 yards (7.53 km), with an average gradient of 1 in 7.86. The steepest gradient on the route is 1 in 5.5, and this occurs in a number of places.
- Llanberis Station(108 metres (353 ft) above sea level)
- Llanberis station includes the company offices and a the locomotive shed and workshop building. The forcourt has recently been changed from a visitor carpark into a cafe/picknick area.
- The two platforms here are dedicated, one for arrivals and the other for departures. Arriving trains empty of passengers then shunt to the other platform. For steam trains, this shunt includes a trip to the water crane and coaling stage outside the locomotive shed.
The first stretch of line is uphill at 1 in 50, steep for a mainline but hardly noticable against the 1 in 6 incline that begins just around the corner.
- Waterfall Station
- Originally built to allow visitor to use the train to travel to a sectacular waterfall close to the line. It had a siding but never a loop and has been closed for many years, but the station building remains.
- A short distance from Waterfall station is a bridge over the river and a gate. This marks the start of the mountain.
- Hebron Station, 1069 ft (326 m)
- The first passing loop. Named after the nearby 'Hebron' Chapel. Passengers are not allowed to leave or join the trains here. The operation of the loop was converted to semi-automatic operation in the early 1990s. It had originally been hoped that agricultural traffic could be carried to and from this station.
- Halfway Station, 1641 ft (500 m)
- As the name suggests, the middle of the line and close to the 'Halfway House' on the nearby footpath. Passengers are not allowed to leave or join the trains here. Steam locomotives take water from a water crane, a large water tank for which is located just above the station. The operation of the loop was converted to semi-automatic operation in the mid 1990s.
- A short distance above Halfway Station is a path that leads down to the 'Halfway House' cafe. Works trains stop here to drop off supplies for the cafe.
- Rocky Valley Halt
- Trains terminate here when the weather is too bad to allow the trains to safely get to the summit. The halt consists of a narrow plaftorm sheltered by a rocky outcrop to the East. Immediately beyond the platform, the line joins the exposed ridge on which it runs about half a mile.
- Clogwyn Station, 2556 ft (779 m)
- The third and final passing loop, it is still manned and retains the original mechanical point levers. Passengers can join down trains here (if there is any space on them). A large water tank near by feeds two water cranes that are provided for emergency use.
- The station is located on the exposed ridge and overlooks the Llanberis Pass. The wind speed is measure here.
- Summit station, 1065 metres (3493 ft).
- This is only 20 metres below the summit of mountain which is at 1085 metres (3560 ft). The station has two platforms that link directly to the summit building and to a path to the actual summit.
- Trains generally use the Summit platforms alternatively.
Train Operation
Trains start from Llanberis Station on the hour and on the half hour. Trains consist of one locomotive pushing a single carriage. It is possible for two trains to run together 'on sight' which involves the second train following after a few minutes (more than 2 but less that 5 minutes) and keeping a safe distance throughout the journey. This is known as a 'Doubler'. All platforms and loops are long enough for two trains running together.
When steam and diesel trains run together, it is normal for diesel to lead up the mountain. This allows the steam train to enter the departure platform and load at its leasure, while the diesel moves across from the arrival platform from a quick turn-around.
Including stops at the passing loops, the train takes an hour to climb to the summit. The average speed of the trains is around 5 mph (8 km/h) and is limited in both directions by independant automatic brakes on the locomotives and the carriages.
Most passengers travel on a return trip (the ticket pricing is biased towards this), this involves being booked onto a specific train for the hour long climb, a half hour break at the summit and then returning on the same train.
Trains only run if sufficent tickets are sold. This is not a problem during the summer if the weather is favourable. The diesel locomotives (and railcar when available) are used first with the steam locomotives being used on trains as required.
Locomotives spend the whole day with the same carriage. Any locomotive can work with any carriage, although carriage No.10 (the most modern) usually runs with a diesel locomotive. On arrival at Llanberis, diesel hauled trains run directly from the arrival platform to the departure platform, load and depart within a few minutes (making one trip every two and a half hours). The Steam hauled trains take at least half an hour to transfer from arrival to departure platform, the time being used to take on fresh coal and water (thus making no more than one trip every three hours). It can thus be seen that the use of diesel locomotives allows more trains to be run with the same number of carriages.
Locomotives push a single carriage in front of them. For safety reasons the carriage is not coupled to the locomotive, although couplings are used during shunting operations (see photogaph on No.6 at Llanberis). An electric cable is run between the locomotive and the carriage, this enables a buzzer to be used to signal between the driver and the guard. The cable is designed to pull free if the locomotive and carriage separate. It was originally intended that each steam locomotive pushed two carriages to the summit, but this has not been the normal practice since 1914.
The first train of the day is the 'Works train'. This carries supplies (including drinking water and fuel for the generator) to summit. It then returns mid morning, with the day befores rubbish from the summit. The train also carries the permanent way gang to where they are working. Most staff at the summit building live there through the summer. Upon its return to Llanberis, the locomotive from this train (always now a diesel) goes straight into service with a passenger train.
It is proposed to rebuild the summit building in the coming years, all materials for this work would also have to be carried up the mountain on the works train.
Locomotives and carriages are all fitted with automatic brakes that are applied mechanically if a set speed is exceeded.
The rack rail
The line uses the Abt rack system, and has a track gauge common to other mountain railways of 800mm (2 ft 7½ inches). The rails are fastened to steel sleepers.
The entire railway is equipped with rack rails. On sidings and around the yard at Llanberis, the rack rail comprises of a single rack bar, but on the running line and through all the loops up the mountain, two rack bars are used. These bars are staggered so that there is a difference of ½ a pitch between the two bars, this is part of the 'Abt System' and helps to reduce the shock of the pinions running along the rack. The joints between bars are also stagger and align with the sleepers (each sleeper supports the rack rail as well as the running rails).
The rack bars are machine cut from a special quality of steel, the profile is not symetrical and the bars must be installed the correct way round. Bars tend to fracture between the fixings. When spotted these breaks are marked and then supported with wedges until the bar can be replaced.
Each locomotive is equipped with a pair of pinions (toothed wheel/cogwheels) on each driving axle. These engage in the rack and provide all the traction (the wheels are free to revolve on the drive axles). The driving axles are spaced so that the pinions on one axle are ¼ of a pitch out from those on the other axle. Combined with the ½ pitch difference in the two rack bars, the smoothest pratical transfer of power is given. In spite of this, the vehicles suffer from very high levels of vibration.
The pinions consist of an outer ring that is eaily replaced. This ring is mounted onto a centre disc and springs between the two reduce shock loads and allow the small movement needed to accommodate joints and curves. The pinion rings have teeth that are symetrical and are turned round to double their working life.
On the way down, all braking is done using the rack and pinion system. Each carriage has pinions mounted on one axle which is used for the manual and automatic braking (all service braking is done by the locomotive.
Following the accident in 1896, most of the line was fitted with 'gripper rails'. These are fixed to either side of the rack rail and are an inverted 'L'. A 'gripper' is fitted to each locomotive, this fits around the gripper rails and holds the locomotive to the rails and prevents the pinion coming free from the rack. The gripper rails are not fitted in the stations and loops nor on the less steep lengths of railway just out of Llanberis and near Waterfall. At the beginning of the sections of gripper rail, the ends are stagger and chamfered to guide the gripper into place.
If a broken rack bar lifts under a locomotive, it can strike the gripper mechanisum and jam under the train. In such an incident, the gripper has to be cut away in order to rescue the train.
It is said that in very high winds, a train can proceed over the exposed sections with the carriage held in to the rails by the gripper. If true, such actions are not routine.
A mechanical failure in 1987 could have caused a repeat of the 1896 accident, however the gripper system worked and held the train on the rails (actually the rails were lift off the ground by the locomotive).
Although no other Abt rack railway use a gripper system, other rack systems do.
The traditional logo for the railway is a pinion ring engaged on a rack bar. At the stations and passing loops, the real items are mounted on steel frames.
Locomotives
The company has owned a total of 12 locomotives, 11 of which remain on the railway.
| No | Name | Date built | Type | Notes |
|---|---|---|---|---|
| 1 | L.A.D.A.S. | 1895 | Steam | Ran away and destroyed on the opening day |
| 2 | Enid | 1895 | Steam | Operational |
| 3 | Wyddfa | 1895 | Steam | Operational |
| 4 | Snowdon | 1896 | Steam | Operational |
| 5 | Moel Siabod | 1896 | Steam | Out of Service |
| 6 | Padarn | 1922 | Steam | Operational |
| 7 | Ralph | 1923 | Steam | Out of Service |
| 8 | Eryri | 1923 | Steam | Out of Service |
| 9 | Ninian | 1986 | Diesel | Operational |
| 10 | Yeti | 1986 | Diesel | Operational |
| 11 | Peris | 1991 | Diesel | Operational |
| 12 | George | 1992 | Diesel | Operational |
Original locomotives - No.1 to No.5
Built specially for the line in 1895 and 1896, these locomotives were manufactured by the Swiss Locomotive and Machine Works of Winterthur. The first locomotives cost £1525.
Numbers 1 to 3 were delivered before the line was open and used on construction work.
The boilers are inclined on the locomotives to ensure that the boiler tubes and the firebox remain submerged when on the gradient, a standard practice on mountain railways (the locomotive always runs chimney first up the mountain). The water gauges (gauge glasses) are mounted half at the centre on the locomotive so that the water level does not change with the gradient. One result of the boilers angle is that the fire hole door is at waist height, requiring the fireman to lift the coal some distance. The boiler is not superheated.
Water is carried in tanks that run the full length of the boiler, but not all this water is for use in the boiler. The tanks are in fact divided into two sections, the smaller front section holding water that is used for cooling when the engine is running down hill.
The drive to the wheels is through a series of levers that allow the pistons to have a longer stroke than the cranks. This is another common feature in mountain railways.
On at least two occations, trials have been made on oil burners, the latest being on No.2 in the late 1990s.
- No.1 LADAS is named after Laura Alice Duff Assheton-Smith, wife of the major landowner in the area. A race horse was also named LADAS and it is after the race horse that the LNER locomotive No.2566was named. This is the same Alice as the class of small Hunslet quarry engines.
- No.2 Enid is named after Laura Alice's daughter.
- No.3 Wyddfa is named after the mountain (in Welsh)
- No.4 Snowdon is named after the mountain (in English)
- No.5 Moel Siabod is named after a neighbouring mountain (Moel is welsh for a round topped or bald topped mountain)
Improved Steam Locomotives - No.6 to No.8
In 1922/1923 a further three locomotives were delivered. Although similar to the first engines in terms of size and power, they have a different design. Again all were built by Swiss Locomotive and Machine Works of Winterthur.
The boilers of these engines are superheated making them more efficent and in place of a lever type regulator, they have a wheel that must be turned 2 ¼ time between closed and fully open.
The drive from the cylinders and to the wheels again uses levers, but in a different pattern. The linkage is fitted within double frames at the front of the locomotive. This results in a locomotives that is far more rigid.
The side tanks are arranged vertically just in front of the cab. No.6 carries the same ammount of water as the earlier engines, but No.7 & No.8 carry enough water to get to the top of the mountain without stopping, if required. There is no separate tank for cooling water as it is drawn from the boiler on these engines.
As the boilers of No.7 & No.8 needed replacing, they were withdrawn from service. This is probably a result of the extra expence of superheaters, added to reduce need for steam locomotives after the introduction of the diesels.
- No.6 Padarn is named after the lower lake at Llanberis. Originally it was named 'Sir Harmood' after the chairman on the company Sir John Sutherland Harmood Banner.
- No.7 Ralph (previously Ralph Saddler) is named after Mr Ralph Saddler, the company's consulting engineer between 1964 and 1977. Originally 'Aylwyn' (until October 1978).
- No.8 Eryri is named after the welsh name for Snowdonia (Eryri = Land of Eagles)
Diesel Locomotives - No.9 to No.12
Built by the Hunslet Engine Company of Leeds to a design and specification developed between themselves and the railway. The design include specially thoughtout features for safety, reliability and appearance. In place of carden shaft drives to the wheels, coupling rods were used to give people something to watch and engine covers were omitted to give a good view of the Rolls Royce diesel engines, themselves chosen for the prestige of the name (or so it is said). The full length canopy above the engine covers not only adds to the distinctive outline but also supports the exhaust silencer. For added safety with only one man in the cab, a 'dead-mans device' is included, a pedal which when release triggers the braking system to bring the train safely to a stand.
During the time between No.9 and No.12 being built, both the locomotive manufacture and the diesel engine manufacturer changed their names, Hunslet becoming Hunslet-Barclay and Rolls Royce diesel engines being sold to Perkins).
It is maintained by the management that the vast majority of passengers do not care whether the trains are powered by steam or diesel locomotives. In the late 1980s comparative figures for the diesels against steam locomotives made it clear that they made ecconomic sense.
| From 1987 | Steam | Diesel |
|---|---|---|
| Round trip fuel costs | £51.00 | £3.05 |
| Locomotive crew | 2 | 1 |
| Round trips per day | 3 | 4 |
| Daily Maintenance (hours) | 1½ | ½ |
The reduced operating costs and reduce costs in having a train standing awaiting sufficent passengers has allowed the operating season to be extended.
- No.9 Ninian is named after the wife of the Chairman (at the time the locomotives were delivered).
- No.10 Yeti was named by local school children following a competition. It was seen as a most suitable name for a mountain creature.
- No.11 Peris is named after the upper lake at Llanberis (Llyn Peris).
- No.12 George is named after George Thomas, 1st Viscount Tonypandy
Railcars - No.21 to No.23
In 1995 three railcars were delivered. These were designed to run as either two or three car trains. When all three railcars are coupled together, there are the maximum length of the train that can fit into the platforms and passing loops. The three railcars are identical.
The drive is diesel electric using a standard industrial generator set mounted at the down hill end of each vehicle. This drives an induction motor through electronic controllers. Unlike any other train on the system, the driver sits at the front when climbing the mountain.
The railcars cannot run as single vehicles for safety reasons (they each have only one set of pinions). So far the railcars have not worked reliably.
Locomotive braking systems
More than any other railway, a mountain railway must have a good braking system and it is a sign of how seriously this has always been taken that right from the opening, each locomotive and carriage has had its own braking system that includes an automatic brake.
- Hand Brakes
All locomotives (and carriages) have a hand brake. These uses brake blocks that clasp drums on either side of the pinions. On the steam locomotives two hand brakes levers are fitted, one for the driver and one for the fireman. These are identical and each can control the descent of a train. If needed a train could be brought down the mountain using the hand brake, but the wear on the drums and blocks would be great and there is the possibilty of damage from the heat generatored. I normal operation, the hand brakes are used for to bring a train to a complete stand (as opposed to controlling the speed) and as a parking brake.
On the diesel locomotives the hand brake is applied by a powerful spring and held off by a hydraulic system.
- Automatic Brakes
Each vehicle with a hand brake, also has an automatic brake that is triggered by the speed. This system uses the same brake blocks and drums as the hand brake.
A centrifugal governor is connected to the pinions by gears. When the set speed is exceeded a lever on the governor hits a lever on the brake valve and the brakes are applied. The system can only be reset (and the brakes released) by the driver leaving the footplate, once the train has stopped.
On the steam locomotives, steam is applied to a small brake cylinder that acts on the drivers side brakes.
The carriages have a similar system that is set to a slightly higher speed than that on the locomotives.
- Compression Brakes
Fitted to the Steam locomotives
- Hydraulic Brakes
Fitted to the diesel locomotives
- Reostatic Brakes
Fitted to the railcars
It is vitally important that all braking is done in a controlled manner as any sudden shocks impose very high loads on the rack rail and pinion wheels, and can cause damage.
History
The idea was first proposed in 1869, when Llanberis was linked to Caernarfon by the London & North Western Railway.
The Snowdon Mountain Tramway and Hotel Company was formed to build the railway.
The Railway was constructed between December 1894 and February 1896 at a total cost of £76,000.
The first passenger train ran on 6th April 1896, but on the return trip, the locomotive derailed leading to the distruction of the locomotive and the death of a passenger. The line remained closed until 19th April 1897.
In 1936 a new building was built at the summit. This was designed be Clough Williams-Ellis, a local architect best know for constructing Portmeirion.
During the second world war, the summit hotel was taken over by the R.A.F. and used as a experimental radar station. To supply this, the trains continued to run to the summit and although passengers were still carried during the early years of the war, they were not permitted at the summit.
Normal service resumed in 1946. It is said that the shortage of coal lead to railwa trying to burn old army boots.
The Llanberis-Caernarfon line closed to passenger in the 1962.
In 1983 the summit buildings were tranferred to the ownership of Gwynedd County Council.
A share issue was made in 1985 primarily to raise money to purchase the first two diesel locomotives.
Between 1986 and 1992 the railway company was involved with the airfield and aviation museum in Caernarfon.
As part of the Centenary Celebrations in 1996 the railway held an enthusiast's weekend in the September. This was one of the few occassions when the public were allowed to visit the railways workshops. Scrap pinion rings were also sold as (rather large) souvenirs. From this time the locomotives were painted in differing liveries, but by 2005 this practice had ended.
The Railway in fiction
The Snowdon Mountain Railway was the inspiration for the Culdee Fell Mountain Railway in The Railway Series by Rev. W. Awdry. It too features a cog railway which climbs a steep mountain. Locomotives push a single coach uphill, and the line's history features one locomotive which ran away.