What is the Simpson Desert?

The Simpson Desert is a large arid desert in central Australia, spanning 176,500 square kilometres across the Northern Territory, Queensland, and South Australia. It is famous for its 1,100 parallel red sand dunes, which run roughly north-west to south-east for hundreds of kilometres and form the largest dune field in the world.

The desert sits on the Lake Eyre Basin, an inland drainage basin that does not reach the sea. Its dunes can rise up to 40 metres high and are typically 100 to 1,000 metres apart, separated by clay pans and gibber plains. The tallest single dune, Big Red, sits near Birdsville on the eastern edge and is a popular four-wheel-drive challenge.

Cecil Madigan led the first non-Indigenous scientific crossing of the Simpson in 1939, naming the desert after Allen Simpson, then president of the South Australian branch of the Royal Geographical Society. The Wangkangurru and Lower Arrernte peoples have occupied the desert for at least 5,000 years and knew of permanent water sources called mikiri, dug deep into the dune swales.

Most of the Simpson is now protected within national parks and conservation reserves: the Munga-Thirri-Simpson Desert National Park (Queensland and South Australia), and Witjira National Park around the Dalhousie Mound Springs. The desert is closed to tourism between 1 December and 15 March each year because of extreme heat, with summer temperatures regularly above 50 degrees Celsius. The Simpson Desert Crossing on the QAA Line is one of the most popular long-distance four-wheel-drive routes in Australia, drawing thousands of remote-touring travellers through Birdsville each cooler season.