The Hann River is a river

River

A river is a natural watercourse, usually freshwater, flowing towards an ocean, a lake, a sea, or another river. In a few cases, a river simply flows into the ground or dries up completely before reaching another body of water. Small rivers may also be called by several other names, including...

 in the Kimberley region of Western Australia

Western Australia

Western Australia is a state of Australia, occupying the entire western third of the Australian continent. It is bounded by the Indian Ocean to the north and west, the Great Australian Bight and Indian Ocean to the south, the Northern Territory to the north-east and South Australia to the south-east...

.

It was named after the first Europe

Europe

Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...

an to discover the river, Frank Hann

Frank Hann

Frank Hugh Hann was an explorer in Western Australia, who in 1897 named Lake Disappointment. Hann was in the area exploring the east Pilbara, around Rudall River. He noticed creeks in the area flowed inland, and followed them expecting to find a large fresh water lake...

, who had seen it during his expedition to the region in 1898 and named it the Phillips River. It was renamed in 1900 by the Surveyor General H F Johnston to honour Hann; a Philips River already existed in the south of the state.

The river rises below below Mount Lacy and Sir John Gorge and then flows in a southerly direction past Mount Elizabeth then crossing the Gibb River Road

Gibb River Road

The Gibb River Road is a former cattle route that stretches almost through The Kimberley between the Western Australian town of Derby and the Kununurra and Wyndham junction of the Great Northern Highway. Like its namesake, which does not actually cross the road but runs nearby at , it is named...

. The river then cuts through the Barnett Range and then passes through the Phillips Range vis Moll Gorge and flows through the Barnett Range until it flows into the Fitzroy River

Fitzroy River

There are three rivers named the Fitzroy River, all in Australia:*Fitzroy River *Fitzroy River *Fitzroy River...

, of which it is a tributary

Tributary

A tributary or affluent is a stream or river that flows into a main stem river or a lake. A tributary does not flow directly into a sea or ocean...

, near Pinnamutta-Murrawong Hill.

The Hann has 12 tributaries including Traine River, Barnett River

Barnett River

The Barnett River is a river in the Kimberley region of Western Australia.The river rises below the Caroline Range near Mount Lacy and then flows south to the west of Mount Elizabeth then through the Barnett River gorge crossing the Gibb River Road near the Mount Barnett roadhouse before flowing...

, Harris Creek, Bella Creek, Macnamara Creek, Crocodile Creek and Grey Mare Creek.

The river has the only known specimens of the grass-like Whiteochloa sp. Hann River, a threatened species of Poaceae

Poaceae

The Poaceae is a large and nearly ubiquitous family of flowering plants. Members of this family are commonly called grasses, although the term "grass" is also applied to plants that are not in the Poaceae lineage, including the rushes and sedges...

, located along its course.

Fish such as the Western rainbowfish, the Kimberley archerfish, Greenway's grunter and the False spotted gudgeon

Eleotridae

Sleeper gobies are members of the Eleotridae fish family, found predominantly in the tropical Indo-Pacific. There are approximately 35 genera and 150 species. While many eleotrids pass through a planktonic stage in the sea and some spend their entire lives in the sea, as adults the majority live in...

have all been found within the river system.