Background John McDouall Stuart led the first successful expedition to traverse the Australian mainland from south to north and return, through the centre of the continent, in 1861–1862. In 1871–1872 the
Australian Overland Telegraph Line was constructed along Stuart's route. The principal road from
Port Augusta to
Darwin was also established on a similar route. A track developed along the route of the telegraph, and by 1888 the road between Adelaide and Alice Springs was well known. Several wells along the route provided water, although these could run dry or be contaminated by dead animals, resulting in sections as long as without water. The route was traversed by motor vehicles in the 1920s. While passable, sections of the road could be sandy, boggy, washed away in the winter, or rugged with boulders. Several creek crossings were required, though few were difficult. North of Alice Springs the road was in comparatively good condition, with sections allowing speeds of up to .
Highway planning and construction With the onset of
World War II, supply roads leading to the north of the country were considered vital by the
federal government. A central north–south highway was planned to connect the
railheads at Alice Springs and
Birdum, with surveying completed in August 1940. The task of constructing the highway was split between the Main Roads Departments The Alice Springs–Birdum road was completed by December 1940, upgraded from an often impassable track to an all-weather sealed highway that could cope with heavy military traffic. The new highway, in conjunction with the railways at either end, reduced the impact of Darwin's isolation. Quick and efficient movement of military equipment and troop was possible, with the road remaining open throughout the wet season. By March 1941, military authorities advocated extending the Alice Springs–Birdum road to Darwin. During the wet season, the road north of Birdum was impassable, which meant that a single railway line was the only connection through to Darwin. Construction was underway by October 1941, once again at a fast pace in an attempt to finish before the next wet season. The road was nearing completion in July 1942, although some sections were yet to be bitumenised.
Speed limits Before 1 January 2007 there was no absolute speed limit in the Northern Territory, but maximum speed limits are now posted along the length of Stuart Highway. Previously drivers were required only to travel at a safe speed for the conditions, meaning the Northern Territory section of Stuart Highway had no speed limits at all. The Northern Territory traffic laws were updated from 1 January 2007 to be similar to the rest of Australia. This included placing a speed limit on all roads ( on major highways such as Stuart Highway) and significantly increasing penalties for speeding. The South Australian section is signposted as outside built-up regions, between Port Augusta and the Northern Territory border. In October 2013 the Northern Territory Government announced a trial period of reverting to an open speed limit on the stretch between Alice Springs and Barrow Creek, beginning 1 February 2014. In September 2015, following the conclusion of the trial, a stretch of the highway had its speed limits derestricted. However, speed limits were restored to this stretch in November 2016; the highest is . In March 2021, the road was closed due to a serious accident 500 km north of Adelaide at Wirraminna where the road collapsed due to burning diesel fuel that melted the road's plastic culverts. Plastic culverts had been used in place of concrete as they were seen as the best material for this particular location as the flood plain of the river is acidic and can destroy concrete culverts. The road was closed while repair works took place. The asphalt also had to be given time to cure and the section of road underwent testing with a
road train. With this now complete, both lanes are reopened with speed restrictions in place. Traffic signage is now in place and road users are asked to take extra care while travelling through this section of road. ==Junctions==