South Island Main Trunk Railway

The designation "South Island Main Trunk" originally referred to only that line between Christchurch and Invercargill.

Construction of the 600 kilometres (370 mi)[2] Main South Line (originally known as the "Great Southern Railway")[1] began in 1865 when the Canterbury Provincial Railways began work on a 1,600 mm (5 ft 3 in) broad gauge line south from Christchurch.

The "Great Public Works Policy" placed a high priority on the completion of the Main South Line.

Although the final portion of this line became the Port Chalmers Branch, most of it was incorporated into the mainline northwards and construction progressed through difficult terrain towards Oamaru.

At the start of the 20th century, work began on a coastal route northwards from Waipara, with the line opened to Parnassus in 1912.

The war also brought a halt to work at the northern end, with the coastal village of Wharanui established as the terminus of the line south from Blenheim.

The coastal route was then chosen and work had only just restarted when the Great Depression began and brought about more severe delays.

World War II brought even more delays, but this time, construction progressed through wartime and the Main North Line was finally completed when the northern and southern ends met at Kaikōura on 15 December 1945.

All other steam-hauled expresses were replaced on 1 December 1970 by the Southerner, which was hauled by DJ class diesel-electric locomotives.