Work is nearing completion on the cross passages which connect the new metro railway tunnels between Chatswood and Sydenham.
Cross passages are an important safety feature of Sydney Metro.
Like on the Metro North West Line, they have been built about every 240 metres along the 15.5 kilometre alignment between Chatswood and Sydenham and are designed to allow customers to move from one tunnel to the other in case of emergency. There are 57 cross passages between Chatswood and Sydenham.
The cross passages are 5.5 metres wide and 6 metres in height and range from seven to 72 metres in length, depending on the distance between the twin tunnels. The longest cross passage is located south of Martin Place, along Liverpool Street.
A remote-controlled excavator was used to dig many of the passages.
Four cross passages connect the tunnels under Sydney Harbour between Barangaroo and Blues Point.