Since 2017, 1.3km of tunnels have been constructed as part of the modernization and expansion of Bank Underground station.
The tunnelling work is now complete, signifying a major milestone in the project.
The size of the station has been expanded by 40% and to do this work included constructing a new southbound running tunnel for the Northern line, with the existing tunnel to be converted into a passenger concourse with six new cross passages linking to the platforms on either side.
Three new escalator barrels have also been excavated to link the Northern line to the DLR and to the new entrance that is being built on Cannon Street, and a new link tunnel will connect the Northern and Central lines.
The tunnelling has seen more than 200,000 tonnes of material excavated from under the City of London, one of the most historic areas of the country.
The work was of an intricate nature and care had to be taken to avoid disrupting any of the 31 listed buildings along the routes of the new running tunnel.
With space at such a premium above ground, extra space was mined below ground to store spoil and allow workers to continue to carry out their work.
By the end of winter, the civil work on the new station entrance on Cannon Street will also be completed, with work on the new platforms also well underway.
Once completed, the new parts of Bank Tube station will greatly increase the space available in the station and reduce journey times considerably.
New moving walkways will connect customers from the Northern line to the Central line, and the new entrance will provide direct access to the Northern line.
Stuart Harvey, TfL’s Director of Major Projects, said: “Bank Tube station is a crucial link between many lines and is one of the busiest interchanges on the Tube network. Work restarted on site again in May and this is a huge milestone for the project. Once completed, there will be more space underground for customers to change from one line to another making journeys quicker and more comfortable for those travelling into the City.”