The North Island Main Trunk is the main railway line in the North Island of New Zealand, connecting the capital city Wellington with the country's largest city, Auckland. The line is long and passes through Paraparaumu, Palmerston North, Taihape, National Park, Taumarunui, Te Kuiti, Hamilton, and Pukekohe.Most of the NIMT is single track with frequent passing loops, built to the New Zealand rail gauge of. The line is double track between Wellington and Waikanae, between Hamilton and Te Kauwhata, and between Meremere and Auckland Britomart. Around of the line is electrified in three separate sections: one section at 1600 V DC between Wellington and Waikanae, and two sections at 25 kV AC: 412km between Palmerston North and Te Rapa and 34km between Papakura and Auckland Britomart.The first section of what became the NIMT opened in 1873 in Auckland. Construction at the Wellington end began in 1885. The line was completed in 1908 and was fully operational by 1909. It is credited for having been an economic lifeline for the young nation, and for having opened up the centre of the North Island to European settlement and investment. In the early days, a passenger journey between Wellington and Auckland could take more than 20 hours; today, the Northern Explorer takes approximately 11 hours.