SISK, the 151-year-old Dublin-based construction company, has won a contract to help build a €600m extension to London's underground train system.

Sisk, along with Spain's Dragados, will build 11.9km of tunnels for trains running in both directions for UK-based Crossrail, the company behind ambitious plans to build a £15bn "super tube".

Boris Johnson, the mayor of London, recently unveiled plans for eight new futuristic Crossrail stations which will be finished by 2018. The stations were designed by architects including Norman Foster and John McAslan and look much bigger and more comfortable than conventional stations.

Crossrail, which is due to start carrying passengers in 2018, will finally see the light of day 29 years after the project was promised. It is planned that an air-conditioned train will run every 2.5 minutes and it will include a link to Heathrow Airport. "We can see the breathtaking benefits it will bring to our city," Mayor Johnson said at the launch

Sisk will build the tunnels running from Limmo Peninsula to Farringdon underground stations; Limmo Peninsula to Victoria Dock and Stepney Green to Pudding Mill Lane, the company said yesterday.

"We are delighted to be working with our joint venture partner Dragados on what will be Europe's largest infrastructure project," said company executive Owen Sisk. "We believe our combined technical and management expertise will successfully deliver this very important addition to Britain's transport infrastructure."