Crossrail TBM Elizabeth has started work on the five-mile section of eastern tunnels between Docklands and Farringdon in central London.
Elizabeth and sister tunnelling machine Victoria were lowered 40 metres underground into a shaft at Limmo Peninsula, next to Canning Town station, last month.
The first of 110,000 concrete segments has now been placed to line what will be Crossrail’s longest tunnel section.
The eastern section of Crossrail will see Elizabeth and Victoria tunnel beneath the River Lea towards the new station box at Canary Wharf where work is already underway to prepare for their arrival and to allow the machines to easily enter the station next year. Both tunnelling machines will then receive maintenance while in the large station box, before continuing their journeys towards Whitechapel, Liverpool Street and Farringdon.
Elizabeth and Victoria are due to arrive at Farringdon in late 2014.
Andrew Wolstenholme, Crossrail’s chief executive, said: “With the start of work on Crossrail’s eastern tunnels we are seeing the biggest construction project in Europe now tunnelling on both sides of the capital.
“This is a significant step towards the huge transport improvements Crossrail will deliver, creating much needed additional capacity and faster new links with London’s major employment areas. By using boats and barges to deliver and remove materials from these tunnels, this will keep thousands of lorries off the road in east London.”