Great Dividing Range, main watershed of eastern Australia; it comprises a series of plateaus and low mountain ranges roughly paralleling the coasts of Queensland, New South Wales, and Victoria for 2,300 miles (3,700 km). Geologically and topographically complex, the range begins in the north on Cape York Peninsula, Queensland. Within that state the ranges’ average elevation is 2,000–3,000 feet (600–900 metres), but they rise as high as 5,000 feet (1,500 metres) in the Bellenden Ker and McPherson ranges and the Lamington Plateau. Farther south the highlands average 3,000 feet; a segment known as the Australian Alps, near the New South Wales–Victoria border, contains Australia’s highest peak, Mount Kosciuszko (7,310 feet [2,228 metres]). The highlands finally bend westward in Victoria to terminate in the Grampians, while a southern spur emerges from the Bass Strait to form the central uplands of insular Tasmania.
The headwaters of a number of Australia’s principal rivers are located in the Great Dividing Range. The Snowy River flows down the steep eastern slope, while the Darling, Lachlan, Murrumbidgee, and Goulburn rivers drain the gentle western slope to join the Murray River.
The range was traversed in 1813 by Gregory Blaxland, W.C. Wentworth, and William Lawson. This initial reconnaissance marked the beginning of European migration, previously inhibited by the highlands, from the east coast into the Australian interior, or outback. The region is now important for agriculture (grazing, mixed farming, fruit growing), lumbering, and mining. The rivers supply large irrigation and hydroelectric projects, while national parks and ski areas attract tourists. Especially popular is the Blue Mountains National Park.