The huge machine that will excavate two City Rail Link tunnels from Mt Eden to the CBD has been unveiled.
The 910-tonne, $13.5 million German-engineered machine will start work in April next year.
The machine can gnaw through 32 metres of ground every day.
It will excavate two 1.6km tunnels from Mt Eden to central Auckland which connect with the tunnels already built from Britomart Station.
The custom-made piece of equipment, engineered in Germany and built in China, was formally named after revered Māori leader and land rights champion Dame Whina Cooper.
It is a tradition that a tunnel boring machine cannot start work until it has been given a woman's name, to honour St Barbara, the patron saint of underground workers, as a sign of good luck and safety for the project.
It was unveiled and blessed in Mt Eden this morning before city rail link workers, councillors, Ngāti Whātua and politicians.
The cutter head at the front of the machine is 7.15 metres wide and the total length is 130m (a rugby field is up to 120m long).
When tunnel excavation starts people will be able to follow its progress via an online tracker which measures the machine's journey below Auckland in real time.
Auckland Mayor Phil Goff said the seven-metre wide, 910-tonne machine was going to do "remarkable things".
Over the next two years it would complete 3.2km of tunnelling, working 24/7.
"No rest for the tunnel boring machine. It will displace up to 1500 tonnes of soil and rock a day," Goff said.
Internet voters were consulted for the naming of the machine, and settled on Dame Whina, who led land protest marchers on a hikoi from Te Hāpua to Parliament in 1975.
Her daughter Hinerangi Cooper commended the naming as a "brave" choice.
She said City Rail Link workers should feel reassured in Dame Whina's company.
"She's a bit like Moses, you know in the Old Testament, when they said he's going to go through the sea and open up the sea. That's what she's doing," she said.
Deputy Prime Minister Grant Robertson said Dame Whina's spirit was reflected in both the mana of the machine and what it would achieve for the city.
"Infrastructure projects are about reducing congestion, so they can move around the city more and pick up Dame Whina's spirit of being a businesswoman, a farmer," he said.
"But they're also about the way we think about our communities. They bring our communities together. We're going to have double the number of people who are within 30 minutes of the CBD, via this project."
Today's the front section of the boring machine was on display, but it will be 130 metres in total.
The remaining parts of the boring machine will be built over the next four months.
Work is also underway to build the first 50 metres of the tunnel from Mt Eden, so the fully-assembled machine can be slotted in and set off on its big underground journey.
Transport Minister Michael Wood said the City Rail Link shows what can happen when mana whenua and local and central government all work together.
"I'm also very pleased about the role that projects like this play in our rebuild from Covid-19 providing real jobs and opportunities for thousands of Aucklanders through the construction of this project."
5000 members of the public have snapped up tickets to see Dame Whina Cooper this Sunday at a 'Boring Day Out'.
The City Rail Link is due for completion in 2024.