City Rail Link opening date officially revealed - but billboards got in first

City Rail Link - a project that has been discussed in one way or another for 100 years - is finally opening.

The CRL is New Zealand's largest transportation infrastructure project, and construction has been going on for the past 10 years.

Transport Minister Chris Bishop and Auckland mayor Wayne Brown made the formal announcement of its opening date of 13 September at one of the new stations - Karanga-a-Hape Station - on Thursday morning.

But that wasn't before billboards announcing the opening date of the $5.5 billion project were put up in error around the CBD in the early morning hours.

An AT spokesperson told RNZ they were put up in error and only supposed to be displayed the official announcement.

"It was a mistake by the billboard provider," they said.

At the announcement, Bishop said he was "thrilled" to announce the opening date, marking a turning point for Auckland.

In just five and a half weeks' time, Bishop said trains would be running all the way through the middle of the city, creating faster journeys and seeing more frequent trains.

People won't have to worry about missing the train because another would be arriving just a few minutes later.

Bishop said the project had been talked about since the 1920s and he was proud to be the minister who got to deliver it.

He said it had not been easy.

Aucklanders have had to live with the project for a decade, disrupting local businesses and closing roads, meaning communities experiences hardships.

But Bishop said once people jump on the first train, they would realise it's all been worth it.

At the announcement, Brown said "finally, we did something ahead of time".

"We announced in this morning, accidentally."

Brown said the project would change the way Auckanders travel and make a better, faster and cheaper way for people to get around.

He said he had strong feelings on how much the project had cost but it was an investment that would ultimately get Auckland moving.

Auckland Transport chief executive Stacey van der Putten said the early announcement of the opening date was disappointing.

"Things happen, it's a bummer, she said.

Van der Putten said it was a "content loading issue" with the advertising supplier and the issue had been raised.

She said mistakes happen and while it happened on the actual day of the announcement, "it's a bummer".

Bishop said, "at the end of the day, who cares?"

He joked that he hoped AT would get some "cost savings on future advertisement".

CRL open days

Auckland Transport, City Rail Link Limited and KiwiRail will be opening the new stations to the public through a series of 'First Look' events. These will be free, ticketed sessions, but numbers will be limited.

They will be held over consecutive Saturdays in August: 8 August - First Look at Maungawhau, 15 August - First Look at Karanga-a-Hape, 22 August - First Look at Te Waihorotiu.

The free tickets for these will be available one week ahead of each event.

At peak, trains will run every five minutes through the city centre and on average around 10 minutes elsewhere on the network. At off-peak the new lines will operate every 15 minutes throughout the day, including weekends, compared with every 20 minutes at present.