The Nihotupu Tramline is a long industrial narrow gauge railway at Nihotupu in the Waitākere Ranges south-west of Auckland in New Zealand, which is being used since 1907 for building and maintaining the dam and water pipeline at the Upper Nihotupu Reservoir. It was used until 24 November 2014 also by the Rainforest Express for tourist excursions, which have been indefinitely ceased due to a risk assessment.