The Waterview Connection tunnel project has formally opened - but drivers won't be able to use the tunnel until early July.
Tens of thousands of people are attending the Sunday morning opening, after which 42,000 walkers will travel through the tunnel.
Newshub reporter Matthew Hutching filmed a Facebook live video showing the inside of the tunnel. Watch the video below for your sneak peak inside.
Some walkers were disppointed to find they could only travel partway through the tunned before being directed to take a fire exit and taken returned to where they came from through the other tunnel.
The Government claims the tunnel will be the biggest change to Auckland's traffic since the Harbour Bridge was opened. The tunnel will be New Zealand's longest, at 2.5 kilometres.
"The Waterview Tunnel is one of the most important infrastructure developments to take place in New Zealand and will help unlock Auckland’s potential as a world class city and secure its future economic prosperity," Transport Minister Simon Bridges said in a press release.
Former Prime Minister Helen Clark tweeted the tunnel was instigated by her Government said it's now time to get on with public transport.
Meanwhile, the Prime Minister got a look at the tunnel by car, tweeting out a video to his followers.