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Transandine Railway

, Argentina and Chile




13 years




Argentina and Chile
Project achievements

Build a railway over the Andes mountains

The Transandine Railway ran across the Andes mountains between the city of Mendoza in Argentina to the city of Santa Rosa de los Andes (now known as Los Andes) in Chile.

Opening in 1910, the 248km-long scheme was a major engineering feat of its day – climbing at often very steep gradients to 10,000ft (3,048m). The route has been out of service since 1984, though there are hopes it could reopen in the future.

The idea for the railway came from entrepreneurs Juan and Mateo Clark. The duo were Chilean brothers of British descent, working through their company Ferrocarril Transandino. Although the Clarks won the concession to build the route in 1874, problems raising finance meant work didn’t begin until 1887.

The Transandine Railway opened in sections between 1891 and 1910 – by then the scheme was owned by the British Argentine railway company. The project joined up pre-existing railways to create a 1,408km link between ports on the Pacific and Atlantic oceans at Buenos Aires and Valparaiso.

Despite passengers having to travel on routes owned by five railways – and with two changes of trains where the rail gauge changed – the journey time was slashed from 11 days by ship to just 36 hours.

The railway was never a commercial success – wagons were lightweight and could only carry limited cargo. Closed in 1984, it’s since been partly dismantled. Although the Argentinian and Chilean governments have agreed to refurbish the route, little progress has been made.

Transandine Railway

Louise Bungay-Azman talks to us about the Transandine Railway, the first railway to link Argentina and Chile across the Andes.

Did you know …

  1. Political tensions between Chile and Argentina from 1977 to 1978 saw all international use of the rail link suspended.

  2. The Chilean government made preparations to destroy sections of the route amid fears Argentina could use the railway to launch an invasion.

  3. As relations between the two countries became less troubled, passenger services along the railway restarted for a brief period, ending in 1979. The last freight train ran on the line in 1984.

Difference the project has made

The Transandine link cut the journey time between the ports of Buenos Aires and Valparaiso from 11 days – sailing round Cape Horn – to 36 hours by rail.

Although the railway was not a commercial success, it helped boost the local economies of towns and settlements along the route.

How the work was done

The Transandine Railway was a combined ‘rack’ and ‘adhesion’ – or friction-based – railway.

A rack railway – also known as a rack-and-pinion railway or cog railway – is a steep grade railway with a third, toothed rack rail, usually between the running rails.

Engineers fit trains with cog wheels along the middle of locomotives and carriages. This meshes with the rack rail as the train goes uphill – effectively pulling it up the slope.

The system allows trains to operate on steep grades above 7% to 10% - the maximum incline for more common friction-based railways. The Transandine scheme used the rack system for steeper stretches of the route.

Challenges during construction included weather conditions. To protect the line from avalanches, engineers built snow sheds alongside the track.

The sheds were mainly timber structures, designed to prevent the tracks from being buried by snow in bad weather.

The method wasn’t always successful – over 55m of snow sheds were buried in an avalanche in 1921, blocking part of the line.

People who made it happen

  • Original idea: Juan Clark, Mateo Clark
  • Construction engineers: Transandine Construction Company

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