this is the moment the northern line extension tunnel was completed
A mile-long tunnel was built in southern London.
The project is the first major expansion of the Metro line since the end of 1990.
Two new nuclear power plants will be opened in 2020, one in the Reconstruction Center of Battersea West power station and the other in Nine Elms to serve the New Covent Garden market.
London Mayor Sadik Khan said: \"Today\'s breakthrough is an important moment for a project that will bring great benefits to southern London.
\"The extension of the North line will not only make it easier to travel to Battersea and Nine Elms, but will also bring thousands of new jobs and families to the area.
This is another good example of why the new infrastructure is so important to London\'s success and the wider economy. ’Two 650-
26 metres (85ft)
In six months, more than 300,000 tons of soil were excavated underground, forming a north-south tunnel.
The tunnels were named Amy and Helen in honor of air pioneer Amy Johnson, the first female pilot to fly alone from the UK to Australia and the first British astronaut, Helen Sharman.
London transport commissioner Mike Brown said I am pleased to welcome the two tunnel mechanics to Kennington after an epic journey.
Both machines had to travel on a challenging, crowded road in south London that included sewers, power cables, Victorian-style --
The Victoria and North Line tunnels have been built.
This achievement brings us one step closer to the delivery of the first major pipeline extension in nearly 20 years.