The Snowdon Mountain Railway is a narrow gauge rack and pinion railway in the UK and winds through spectacular scenery to take visitors the 4.7miles from Llanberis to the 1,085m Summit of Snowdon, the highest mountain in Wales.

In 1894, work began on the construction of the Snowdon Mountain Railway. It had taken over 20 years to get to this point, after local opposition from the landowner, Mr Assheton-Smith, was finally lifted. 

The first five steam locomotives were ordered from Switzerland, where they had expertise in carrying passengers up and down a mountainside. Three of these are still in operation today, which is testament to the quality of their original manufacture. 

Construction began with the engineers for the railway, Sir Douglas Fox and Mr Andrew Fox alongside the contractors, Holme and King of Liverpool who were to build the Llanberis and Waterfall Viaducts that cross the Afon Hwch river. Within a year, over 50% of the earthworks were completed and track laying began from the Llanberis base and working upwards, to ensure the correct alignment of the rack. With the trains already delivered, they were pressed into action to deliver men and materials to the moving construction site and by January 1896, the first trains reached the summit. 

The final construction cost £63,800 (equivalent to around £7.5m today) and the grand opening was scheduled for Easter 1896. Sadly, there was an accident on the opening day and it was delayed. The subsequent enquiry concluded that post construction settlement, combined with the weight of the train and passengers was the problem. They further recommended, that going forward, trains could only run at around 75% capacity. This prompted the design and introduction of new lighter carriages for the service.

In 1986, ninety years after the original steam trains entered service, two diesel locomotives were added to the fleet. They were equipped with 320hp Turbocharged Rolls Royce Engines and cost £250,000 each. They proved so reliable that three more were added over the next four years. Soon after their introduction, the Diesel engines took on the large majority of the passenger journeys. On an average running day today, the diesels make 16 journeys to the summit and the steam four. It’s so popular that they run seven days a week.

A plan for new carriages

For as long as it’s been carrying passengers, weight has always been the limiting factor on the running capacity of the railway. So, in 2011, when Garmendale took the first call from Mike Robertshaw, the Senior Engineering Manager at Snowdon Mountain Railway, it was with a brief to create new, lighter carriages for the diesel rolling stock. 

For ease of implementation, a decision had been made to work with the bogies made by Hunslett, as their braking systems and bogies had already been signed off for use on the track. This would save over two years on the delivery of the completed carriages, so was a great shortcut. 

One year on and the new carriages were delivered to Snowdon in October 2013 for their maiden voyage. 

The new carriage design used a revolutionary lightweight material, designed to save weight and create a warm insulated carriage for comfort, with huge glass areas for visibility and wide opening doors for ease of passenger access. 

Soon after the project was completed, Mike Robertshaw, recapped on the how the project had run from his perspective. 

“Until 2013 the carriages had been in service since 1896. They had twice been re-bodied in house during 1951 and 1957 and were past their useful life. 

We issued the final specification in 2011 and two compliant bids were received. One bid proposed an aluminium bodied carriage and the other from Garmendale, a novel GRP honeycomb body. Both options used a development of the latest braking technology from Hunslet Engine Company on their bogies. 

Building the new Snowdon Mountain Railway carriages

After several months of review and discussions with the tenderers it was decided to work with Garmendale. They would build the chassis and bodies, including fit-out of the carriage interior and external livery. The bogies and braking system were to be provided to Garmendale by Hunslet. 

The GRP honeycomb body was felt to have maintenance advantage as well as inherent insulation properties and provide a corrosion free structure that would be important in the conditions in which it would have to operate.

We carried out an extensive engineering review and although the approach was novel and the materials untried in railway vehicle manufacture, Garmendale provided test pieces, demonstrated fabrication techniques and the final paint finish, all before the contract was finally placed. 

During the design phase, weight of the new carriages was a major consideration as the new carriage would potentially be heavier than the existing stock. The Garmendale solution actually reduced the weight of the carriages, whilst increasing passenger capacity.”