Telegraph links were established between Adelaide, Melbourne and Sydney in 1858 and extended to Brisbane in 1861 and Tasmania in 1869.

The network fostered the growth of an intercolonial market and strengthened ties between the colonies. In 1872 the Overland Telegraph Line linked Adelaide to Darwin where it joined a submarine cable to Java and the cable system linking Asia and Europe.

This enabled rapid communication between Europe and Australia for the first time. The Overland Telegraph Line was possibly the greatest engineering feat of 19th-century Australia. It crossed almost impenetrable, unexplored land that just a decade before had claimed the lives of explorers, Burke and Wills.

Messages that had once taken three months to reach London now took less than a day.

An additional telegraph link to Perth was completed in 1877.

Image: Planting the First Pole in the Overland Telegraph Line, circa1870, National Library of Australia