To cheers from construction workers, a giant boring machine named Florence burst through the final metres of rock in Sydney's north west on Thursday, completing the twin 15-kilometre tunnels that will form part of Australia's largest public transport project.
The end of the tunnelling at the site for a new station at Cherrybrook led Premier Mike Baird to declare that the $8.3 billion Sydney Metro Northwest rail project was "ahead of time and under budget".
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The making of the Northwest tunnel
As tunneling work concludes on the Sydney Metro Northwest, we take a look at the impressive works in time-lapse. Vision: NSW Transport.
"We are not only investing in making sure the existing system is as strong and positive as it can be, but at the same time building additional capacity [into Sydney's public transport]," he said.
The twin rail tunnels run for just over half of the route of the new metro line from Cudgegong Road in the north west to Chatswood. Since September 2014, four boring machines have excavated more than 1.7 million tonnes of crushed rock, most of which was sandstone and shale.
![A giant boring machine named Florence bursts through rock at Cherrybrook in Sydney's north west on Thursday.](/web/20161006195031im_/http://www.smh.com.au/content/dam/images/g/m/5/z/0/u/image.related.articleLeadwide.620x349.gm5j59.png/1452752704470.jpg)
Eight new stations are to be built on the Northwest metro line, and driverless, single-deck trains are expected to begin running on it by early 2019. Once completed, the line will include a 4-kilometre "Skytrain" viaduct from Bella Vista to Rouse Hill.
The Northwest project is the first stage of a 65-kilometre metro line that will eventually connect to Bankstown in the city's southwest via stations in the Sydney CBD.
The second stage from Chatswood to Bankstown involves digging another two 15-kilometre tunnels via new stations at spots such as Pitt Street in the CBD and will cost more than $10 billion.
Last month, the government chose Waterloo over Sydney University as the location for a station on the metro line. The exact site for the train station has yet to be determined.
![NSW Premier Mike Baird declared the $8.3 billion Sydney Metro Northwest rail project "ahead of time and under budget".](/web/20161006195031im_/http://www.smh.com.au/content/dam/images/g/m/5/z/1/b/image.related.articleLeadwide.620x349.gm5j59.png/1458713970173.jpg)
The team steering Sydney Metro expects to hand a business case for the second stage of the public transport project to the Baird government within the next few months.
Transport Minister Andrew Constance said the tunnelling for the Northwest line was two months ahead of schedule and the new metro project would result in greater capacity across the network.
"It is a case of patience but there is investment happening," he said.
Florence was named after Australia's first female architect and civil engineer, Florence Taylor.