Kaimai Tunnel Kaimai Tunnel The Kaimai Tunnel is a railway tunnel through the Kaimai Range in the North Island of New Zealand. Since it was opened in 1978, it has held the title of longest tunnel, at 8.879 kilometres, in New Zealand, assuming this distinction from the previous title holder, the Rimutaka Tunnel. It is part of the Kaimai Deviation, which was constructed to bypass the old route of the East Coast Main Trunk Railway through the Karangahake Gorge (part of which has been preserved as the Goldfields Railway). The Kaimai Deviation is a 24 km line between Waharoa and Apata, including
Rimutaka Incline 13 September 1871. Julius Vogel, Colonial Treasurer, travelled to England to raise finance for a major public works programme for railway construction. Vogel returned via the United States, where he studied rail systems. After the act of parliament was passed, a survey party set out to make preliminary investigations of possible routes for a railway over the Rimutaka Range (spelled Rimutaka Range, since 2017). These were complete by December 1870, the party having investigated four routes. A commonality between all the proposals was the section from Upper Hutt to Kaitoki (later Kaitoke). Between Kaitoke and the Wairarapa, the four proposals