Work has begun on the final section of tunnelling for the HS2 railway into central London, with engineers launching the project’s last giant tunnel boring machine from Old Oak Common in Acton towards Euston station.
The 1,624-tonne machine, named Karen, started excavation on Monday (16 March 2026) from the HS2 station site at Old Oak Common in Acton and will travel 4.5 miles to complete the second bore of the Euston tunnel. HS2 said the launch marked a significant milestone for the high-speed rail project linking London and the West Midlands.
The machine is named after Karen Harrison, one of the UK’s first female train drivers. To mark the occasion, two current drivers from Avanti West Coast, Hayleigh Richardson and Vicky Knight, were invited to operate the controls alongside engineers working on the project.
HS2 said the twin-bore tunnel will allow high-speed trains to run directly into Euston, increasing capacity on the rail network and cutting journey times. The government has also argued that a new HS2 station at Euston could act as a catalyst for regeneration in the surrounding area.
Lord Hendy, the rail minister, said: “Today’s launch brings HS2’s journey to Euston another step closer to reality.”
The railway is currently undergoing what HS2 describes as a “reset” aimed at bringing greater certainty to the project’s costs and timetable.
