Having driven a total of 6·8 km from Chamartín, the 2200 tonne earth pressure balance TBM broke through into an access shaft sunk close to the former trainshed of Atocha station.
Boring of the 10·4 m diameter tunnel took nine months at a rate of 25 m a day. The tunnel runs at a average depth of 45 m, crossing under the two existing rail tunnels between Charmartín and Atocha as well as eight metro lines.
Work on related civils, tracklaying and tunnel safety equipment totalling €206m will begin within the next few months. Electrification, signalling and telecommunications work is expected to go out to tender shortly.