Rail route straight through the Cantabrian Mountains

Two key tunnels for the emerging high-speed rail line between Madrid and Asturias in north-west Spain are being carved by heavy-duty machinery. When complete, they will speed up transport across difficult mountainous terrain.

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Located in the country’s Castilla y León and Asturias Autonomous Communities, the Pajares tunnels are being constructed under a project partly funded by the EU. They form part of European plans to enhance high-speed rail travel in south-west Europe.

Two new tunnels

Plans for the high-speed line between Madrid and Asturias, passing via León, were first set out in European legislation in 1996. They were part of a scheme to modernise rail transport across the Iberian Peninsula, in line with the development of railways across the rest of Europe.

Under a major project for the Madrid-León-Asturias high-speed line for passenger and cargo trains, work is proceeding on the Pajares route and specifically two subsections: La Robla-Túneles de Pajares and Túneles de Pajares-Sotiello-Campomanes-Pola de Lena. This route passes through the Catabrian Mountains, a natural barrier to transport between the Principality of Asturias and central Spain.

The project’s goal is to build new and straighter tunnels along a 25-km stretch of line, part of the new Pajares bypass section totalling almost 50 km. This new rail bypass will replace an earlier one opened in the late 19th century.

Work is to be done on four subsections. In the first phase, contractors will move earth and build new tunnels and viaducts. Cross-links will also be installed between the two parallel single-track tunnels at regular intervals. The latest equipment will be used, including tunnel-boring machines capable of lining the walls immediately after the holes are bored. In the second phase, work will focus on installing track, electrification and the installation of communication and signalling equipment.

Boost for travellers and tourists

When completed, the new Pajares bypass and its tunnels are expected to be an important part of the high-speed rail line from Madrid to Asturias. The new route will be more comfortable and allow faster travel between cities such as Valladolid, Palencia, León, Oviedo and Gijón, in most cases more than halving journey times.

Further benefits of this sleek new line are expected to be easier access for tourists to the north-west of Spain and encouragement for local motorists to abandon cars in favour of the train.

Draft date