Rail transport in South Australia

The first railway in colonial South Australia was a horse-drawn tramway from the port of Goolwa on the Murray River to an ocean harbour at Port Elliot in 1854. Today the state has 1,600 mm (5 ft 3 in) broad gauge suburban railways in Adelaide, a number of country freight lines, as well as key 1,435 mm (4 ft 8 ¹⁄₂ in) standard gauge links to other states.

In 1847, the South Australian Parliament passed an act confirming the adoption of the standard gauge of 4 ft 8 ¹⁄₂ in (1,435 mm) for Australia. South Australia was the first state to do so. In 1848 the Colonial Secretary in London, Lord Grey, recommended the Australian colonies all adopt standard gauge. However, this advice got muddled up.

The first of the main line railways in Adelaide was built in 1856 between the city and the port, in the 5 ft 3 in (1,600 mm) broad gauge, to maintain compatibility with Victoria after a change from 4 ft 8 ¹⁄₂ in (1,435 mm) by New South Wales' which changed back before it built its railways. The main line to Melbourne was opened after a bridge was built at Murray Bridge in 1886. It was the first railway line between colony capitals to not have a break-of-gauge. It was also the last of these to be converted to standard gauge in 1995.

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