Auckland will open its first underground railway to passengers on Sunday 13 September, marking the completion of New Zealand’s largest transport infrastructure project and the biggest change to the city’s rail network in more than a century.

The City Rail Link (CRL), a 3.45km twin-tunnel underground railway connecting three new stations at Te Waihorotiu, Karanga-a-Hape and Maungawhau, will convert Waitematā Station (formerly Britomart) from a dead-end terminus into a through-station, allowing trains to run directly across the city centre for the first time.

The NZ$5.5 billion project has been jointly funded by the New Zealand government and Auckland Council, and delivered by City Rail Link Ltd in partnership with Auckland Transport, KiwiRail and operator Auckland One Rail. Main construction was carried out by Link Alliance, a joint venture of Vinci Construction Grands Projets, Downer, Soletanche Bachy, WSP, AECOM and Tonkin+Taylor.

First services will depart from around 5am on opening day, operating to a special one-off timetable rather than the standard Sunday pattern that will follow. Trains from across the network, including Henderson, Swanson, Puhinui, Manukau, Pukekohe, Parnell and Newmarket, will run through the new tunnels from early morning.

Auckland Transport chief executive Stacey van der Putten said the organisation was preparing for high demand throughout the day.

“We know many people will be keen to be on one of the first services, and we encourage people to start their first journey from their local station,” she said. “Trains from right across the network will be travelling through the CRL from early that morning, so there will be plenty of opportunities to be part of this historic day.”

Once fully operational, CRL is expected to carry around 90 per cent of all Auckland train services and will double the number of people living within a 30-minute train journey of the city centre. Peak frequencies through the city centre will increase to a train every four to five minutes, with off-peak services running every 15 minutes across the network, including weekends, up from the current 20-minute interval.

However, Auckland Transport has confirmed the railway will initially operate a transitional timetable, with peak frequencies outside the city centre similar to current levels before increasing over roughly six months as confidence in the new network builds, an approach the organisation says is consistent with international practice on comparable projects.

Fleet and workforce readiness

Auckland Transport has completed a NZ$330 million fleet expansion, jointly funded by NZ Transport Agency Waka Kotahi and Auckland Council, taking the total electric multiple unit fleet to 95 units following delivery of the final CAF-built train in February. The existing fleet of 72 units has also been retrofitted with CRL-compatible systems including operational connectivity, LED lighting, door sensors and emergency alarms.

Operator Auckland One Rail has certified 264 drivers to operate CRL routes and completed station familiarisation training for 195 train managers, with a further 101 customer service staff undergoing training ahead of opening.

Mobile network operators One NZ, Spark and 2degrees have collaborated for the first time to install shared 4G and 5G infrastructure throughout the tunnels and stations, comprising more than 350 radio transmitters and 74km of cabling, with One NZ leading the physical build alongside technology partner Nokia.

Extensive testing and emergency response programme

The project has undergone what City Rail Link Ltd describes as an extensive testing and commissioning programme, including more than 1,600 test train journeys since dynamic testing began in February 2025, and successive rounds of network-wide timetable testing that required full and partial closures of the Auckland rail network through 2025 and 2026.

A large-scale emergency evacuation testing programme ran between April and June 2026, involving around 200 personnel, more than 50 emergency service vehicles and 1,400 volunteer passengers across 15 live exercises, with scenarios including train fires, derailments and multi-station evacuations. A final multi-agency exercise simulating a train fire near Te Waihorotiu Station, involving Fire and Emergency New Zealand, New Zealand Police and Hato Hone St John, took place in the week of 24 August.

City Rail Link Ltd chief executive Patrick Brockie said the underground environment, with tunnels more than 40 metres below ground in places, had required specialist planning.

“I want to thank every single person who’s played a part in this mammoth effort to ensure Aucklanders can travel with confidence, knowing they’ll be well taken care of should the unexpected ever happen in our new stations and tunnels,” he said.

Station precincts and wider network upgrades

Alongside the underground works, Auckland Council and Auckland Transport have delivered above-ground renewal programmes at each station precinct, including the reopening of Albert Street as a two-way corridor with dedicated bus lanes in November 2025, and completed public realm upgrades around Waitematā and Karanga-a-Hape stations.

The opening has been supported by KiwiRail’s wider Rail Network Rebuild programme, which the company says has replaced more than 80km of rail and renewed 70km of drainage and 30km of foundations across the network over five years. KiwiRail says the completed upgrades mean no full network closure will be required this coming summer, compared with 33 days of full closure the previous year.

Public interest in the project ahead of opening has been significant. A series of ticketed First Look events at the three new stations during August drew more than 43,000 visitors, with local business associations around Maungawhau, Karanga-a-Hape and Te Waihorotiu reporting some of their strongest trading days on record.

Transport minister Chris Bishop said the project represented one of the most significant transport investments in New Zealand’s history. “The CRL will fundamentally change the way Auckland’s rail network operates, with faster journeys, more frequent services, and better connections across the city,” he said.