Auckland's City Rail Link project is one step closer to completion, with all tunnelling now complete.
A boring machine broke through at Te Waihorotiu Station on Wednesday night, which was a moment 13 months in the making.
It's the final of four tunnel breakthroughs made by the boring machine, which proved quite the spectacle.
"[It] means the world really - it's a once-in-a-lifetime thing to see," one worker told Newshub.
Dame Whina Cooper - the giant boring machine - worked 24/7 to reach this milestone. She was operated by 12 underground crew and a dozen above ground.
"I think it was appropriate that the tunnel boring machine was named after Dame Whina Cooper. No matter what stands in the way - it just keeps going forward," Local Government Association Minister Kieran McAnulty said.
It was a moment so significant, her whānau were there to witness it - along with Auckland's Mayor.
"When we open, there will be double the capacity of heavy rail into Auckland," Phil Goff said. "We'll be able to handle 54,000 people an hour."
The twin tunnels are 1.6 kilometres long and will link Britomart to a re-developed Maungawhau/Mt Eden train station.
While under construction, the tunnel boring machine placed 2118 segment rings and removed 260,000 tonnes of spoil.
More than 2000 workers have contributed to the project, with some coming from all around the world.
"I've come from the UK, so being able to be part of a project of this scale in little New Zealand is absolutely fantastic," another worker told Newshub.
But getting here has been no easy feat. COVID-19 has caused a major disruption, grinding the pace of production to a crawl.
"I have never encountered the level of uncertainty in my 40 years in the industry," City Rail Link chief executive Sean Sweeney said.
"To have achieved what this team of 2000 people have in the face of a global pandemic, multiple lockdowns, restricted COVID-working conditions and multiple other challenges is nothing short of extraordinary."
The multi-billion dollar project was originally set to finish in 2024 but there's uncertainty on whether that deadline will be met.
"We're still working that out," Sweeney said.
But there is something that is certain.
"This project will be here for decades and decades, serving the people of Auckland," Goff said.
