Sydney’s new metro railway will run through purpose designed and built tunnels.

A number of factors determine the tunnel route and alignment. These include:

  • the location, depth and structure of the stations
  • vertical track grade
  • rock conditions
  • track curvature, to allow train speeds of up to 100 kilometres an hour
  • the physical constraints of the route, including crossing under Sydney Harbour.

Stage 1: Sydney Metro Northwest

Tunnelling finished in January 2016 on Australia’s longest railway tunnels – twin 15 kilometre tunnels from Bella Vista to Epping as part of Stage 1 of Sydney Metro.

Stage 2: Sydney Metro City & Southwest

Tunnelling started in October, 2018 on the twin tunnels from Chatswood to Sydenham, including under Sydney Harbour and through the Sydney CBD.

https://www.sydneymetro.info/tunnelling