Commuters can now take the train directly between Pukekohe and Auckland CBD.
A major section of Auckland's rail line that had been shut for more than two years re-opened on Monday.
Pukekohe Station closed in August 2022 for KiwiRail to electrify the rail line between Pukekohe and Papakura and complete maintenance work in preparation for the City Rail Link set to open in 2026.
People travelling from Pukekohe have had to take a bus to Papakura and catch the train from there to get to Britomart, Auckland Transport director of public transport and active modes Stacey van der Putten said.
"Right now there is a bus replacement service connecting to Papakura Station so they [commuters] will save 25 minutes on their journey by having that direct connection."
The Southern Line was previously only electrified as far as Papakura, and Pukekohe passengers had to transfer between an electric train and a diesel train to get to the city centre.
Pukekohe to Papakura had been the missing link in the city's electrified network, van der Putten said.
"It is now a one-seat journey for people travelling from Pukekohe.
"And it is a nicer experience sitting on an electric train than a diesel one. It is quieter, smoother, they [commuters] will notice a difference."
Auckland Transport said 800 mast structures were installed to support almost 130km of overhead electric line to power electric trains between Pukekohe and Papakura.
Three new stations along the section of track - Drury Station (Drury Central), Ngākōroa Station (Drury West), and Paerātā Station (Paerata) - were also going to be built by the end of 2026.
In the next 30 years, 120,000 more people were projected to live in South Auckland.
More connections to the public transport network were needed to keep up with the region's growth, van der Putten said.
"Right now, there are not a lot of transport options for communities out there and this will make a huge difference."
The Te Huia train service from Hamilton would soon also stop in Pukekohe, she said.
"We are working with the Waikato Regional Council to make that a smooth connection."
In total, 183km of Auckland's rail network had now been electrified.
Van der Putten acknowledged there had been a lot of disruption to the network recently, particularly for South Aucklanders.
"The electrification was one thing, and a huge thing at that, there was also station re-development and rail and track replacement work. A tremendous amount has been done to improve the resilience of the network.
"Once the City Rail Link comes we will have a more reliable, frequent, and connected network for Aucklanders to get around their city."
Train services now run every 20 minutes between Pukekohe Station and Britomart along the Southern Line until 7pm, when they run every 30 minutes.
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