Opened in 1908, the North Island Main Trunk Railway linked Auckland with Wellington, Taranaki and Wanganui. Southbound trains from Taumarunui climb 636 metres in only 52 kilometres to National Park, the steepest gradient being 1 in 50, laid out in the form of an ascending spiral, incorporating a complete circle, three horseshoe curves, and two short tunnels.



Passenger excursions to view the spiral  trip between National Park Village and Auckland on Overlander service with panoramic viewing windows. Alternatively, you can see three levels of the Spiral from a viewing platform at Raurimu.