What is the Great Dividing Range?

The Great Dividing Range is a vast chain of mountains, hills, and plateaus running about 3,500 kilometres along the eastern coast of Australia, from Cape York Peninsula in far north Queensland through New South Wales and Victoria to the Grampians in western Victoria. It is the third-longest land-based mountain range in the world, after the Andes and the Rockies.

The range separates the narrow eastern coastal plain, where most Australians live, from the vast inland plains and the Outback. It has driven Australian settlement patterns since 1788. Sydney was hemmed in by the Blue Mountains (part of the range) until Gregory Blaxland, William Lawson, and William Wentworth crossed them in 1813, opening the western plains to pastoralism. The range continues to define New South Wales watersheds: rivers flowing east of the divide reach the Pacific quickly, while rivers flowing west feed the Murray-Darling Basin, the largest river system in Australia.

The range is not a single sharp ridge but a complex of mountain ranges, uplifted plateaus, and valleys. Notable parts include the Atherton Tableland in Queensland, the New England Tablelands and Blue Mountains in New South Wales, the Australian Alps spanning New South Wales, the Australian Capital Territory, and Victoria, and the Grampians (Gariwerd) in western Victoria. Mount Kosciuszko in the Snowy Mountains, at 2,228 metres the highest point on mainland Australia, is part of the range.

The Great Dividing Range is geologically ancient. Most of it was uplifted during the Carboniferous and Permian periods more than 250 million years ago, and erosion since has reduced what may once have been Himalayan-scale peaks to the rolling country seen today. The range hosts a chain of national parks and important catchments that supply drinking water to Sydney, Canberra, Melbourne, and Brisbane.