Tunnelling has started on the Paris metro’s line 14 extension from St Lazare to Mairie de Saint-Ouen.
The tunnel boring machine (TBM), named Magaly, was launched at a ceremony attended by French transport minister Alain Vidalies and Paris mayor Anne Hidalgo.
The line 14 extension will involve the construction of 5.8km of tunnels and four new stations.
The extension, which is scheduled to be operational by 2019, is the first phase of the Grand Paris Express project.
As well as the extension of existing metro lines, the Grand Paris Express project will consist of a ring route around Paris (line 15) and lines that serve developing neighbourhoods (lines 16, 17 and 18).
The project is expected to be complete by 2030.