The Longest River: Australia's longest river is the Murray-Darling River, in New South Wales, which flows for 2,911 miles (4,685 km) into the Indian Ocean.

http://www.enchantedlearning.c...

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The Longest River: Australia's longest river is the Murray-Darling River, in New South Wales, which flows for 2,911 miles (4,685 km) into the Indian Ocean.

http://www.enchantedlearning.c...

I think the confusion stems from Murray-Darling River is drying up...

"The Darling River basin covers an area of 699,000 sq kms (sq miles) and makes up 70 percent of the Murray-Darling Basin.

The pumping of groundwater had also resulted in the loss of surface flows in the river of 74,000 megalitres a year and this will rise to 191,000 megalitres as extraction increases.

The report said that unless river management was changed and the over-allocation of water reduced then the the drying up of the Darling River presented "a serious risk to long-term socio-economic sustainability" of farms and towns on the river."

web source:

http://www.planetark.com/daily...

The Darling is the longest - the Murray is the largest, and together they make the Murray-Darling River system, which by the way is drying up, but is the largest river system in Australia!

What is the Longest River in Australia?
The longest river originates in Queensland and is called the Darling River. It is 1,700 miles long (2736km).

Australia’s longest river system is the Murray-Darling River. It flows for 2,911 miles (4684km) across southeastern Australia from the Snowy Mountains to the Southern Ocean.
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What is the Longest River in Australia?
The longest river originates in Queensland and is called the Darling River. It is 1,700 miles long (2736km).

Australia’s longest river system is the Murray-Darling River. It flows for 2,911 miles (4684km) across southeastern Australia from the Snowy Mountains to the Southern Ocean.
http://answers.yahoo.com/quest...Longest Continuous River System

The Murray River and its tributary, the Darling River, are the main rivers in the Murray-Darling River Basin. This drainage basin comprises the major part of the interior lowlands of Australia, covering more than one million square kilometres, or about 14 per cent of Australia.

The Darling River flows south from the junction of the Culgoa and Barwon rivers. Although the Culgoa is longer than the Barwon, the source of the Darling is generally agreed to be the Barwon River as it has the greater volume of water. The headwaters of the Darling can be traced to the MacIntyre River, which starts in the Great Dividing Range, and forms part of the border between NSW and Queensland. It eventually flows south into the Barwon. The Barwon-MacIntyre section is sometimes referred to as the Upper Darling. When measured from its source in Queensland to its mouth on the coast south-east of Adelaide, the Murray-Darling river system is 3370 kilometres long, about half the length of the world's longest river, the Nile.

Name: Longest Continuous River System - Murray-Darling River System State:Queensland / New South Wales / South Australia
Length :3370

Name: Longest River - Murray River
State: New South Wales / South Australia
Length:2520

Name: Darling (from the Murray River to Culgoa River)
State: New South Wales
Length: 1390

http://www.ga.gov.au/education...