Rail transport in New Zealand consists of a network of 1,067 mm (3 ft 6 in) narrow gauge railway lines in both the North and South Islands. Rail services are focused primarily on freight, particularly bulk freight, with limited passenger services on some lines. Only Auckland and Wellington have urban rail systems, both of which are being upgraded and expanded.

The railway network was initially constructed by the provincial governments of New Zealand from 1863 onwards. New Zealand's first public railway was opened in that year at Ferrymead by the Canterbury Province. The first steam-powered railway operated between Christchurch and Ferrymead.

The Canterbury Provincial Railways were built to the broad gauge of 1,600 mm (5 ft 3 in). On 5 February 1867, Southland Province opened a branch from Invercargill to Bluff to the international standard gauge of 1,435 mm (4 ft 8 ¹⁄₂ in). From 1870, the central government of Sir Julius Vogel proposed infrastructure including railway development, to be funded by overseas loans of £10 million. The central government also adopted a national gauge of 1,067 mm (3 ft 6 in). The first narrow-gauge line was opened on 1 January 1873 in the Otago Province, the Port Chalmers Branch under the auspices of the Dunedin and Port Chalmers Railway Company Limited. Auckland's first railway, between Auckland and Onehunga, opened in 1873. Vogel also arranged for Brogdens of England to undertake several rail construction contracts, to be built by "Brogden's Navvies" recruited in England.

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