London Underground’s Northern line extension comes into service

1.1bn project adds nearly two miles of tunnel and two new stations - Nine Elms and Battersea Power Station

The first major addition to the London Underground this century comes into service on Monday, when the Northern line extension opens to carry passengers to new stops at Nine Elms and Battersea Power Station.

Taking six years of construction and testing, and a longer period again of design and planning, the 1.1bn project - adding nearly two miles of tunnel as well as the two stations - has put the dramatically changing area of south London on the Tube map.