What is the longest river in Australia?

What is the longest river in Australia? The Murray River. Commonly called the River Murray in South Australia, it runs through or along New South Wales, Victoria and South Australia before reaching the Southern Ocean through the Murray Mouth and nearby lakes.

The Murray rises in the Australian Alps and flows westward across southeastern Australia. It is about 2,375 kilometres long in commonly cited national river rankings. Its course forms much of the border between New South Wales and Victoria, although the legal boundary follows the river’s southern bank.

The Murray is the central river of the Murray–Darling Basin, Australia’s largest drainage basin and one of its most important agricultural regions. Major tributaries include the Murrumbidgee, Darling and Lachlan rivers. The Darling is a major tributary, not the longest river itself.

A subtle source of confusion is the distinction between a river and a river system. If the longest connected tributaries are counted together, the Murray–Darling system is far longer than the Murray alone. For the standard quiz question asking for Australia’s longest river, however, “Murray River” is the canonical answer.