Walyunga National Park is a national park in 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...

 (Australia

Australia

Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...

), 35 km northeast of Perth

Perth, Western Australia

Perth is the capital and largest city of the Australian state of Western Australia and the fourth most populous city in Australia. The Perth metropolitan area has an estimated population of almost 1,700,000....

 along the Great Northern Highway

Great Northern Highway

The Great Northern Highway is a generally north-south Western Australian highway which links the state's capital Perth with its most northern port, Wyndham. It is in length, with being National Highway...

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The park is situated just behind the Darling Scarp

Darling Scarp

The Darling Scarp, also referred to as the Darling Range or Darling Ranges, is a low escarpment running north-south to the east of the Swan Coastal Plain and Perth, Western Australia...

 in the Darling Range spread over a steeply sided valley. The Swan

Swan River (Western Australia)

The Swan River estuary flows through the city of Perth, in the south west of Western Australia. Its lower reaches are relatively wide and deep, with few constrictions, while the upper reaches are usually quite narrow and shallow....

-Avon River

Avon River (Western Australia)

The Avon River is a river in Western Australia. It is a tributary of the Swan River totalling 280 kilometres in length, with a catchment area of 125,000 square kilometres.-Catchment area:...

 runs through the park and the Avon Descent

Avon Descent

The Avon Descent is an annual, two-day, white water event involving both paddle craft and small motor boats. It runs from Northam to Perth, Western Australia along the Avon and Swan Rivers, and is held in August of every year....

 passes through a set of rapids along this section. The area is dominated by granite

Granite

Granite is a common and widely occurring type of intrusive, felsic, igneous rock. Granite usually has a medium- to coarse-grained texture. Occasionally some individual crystals are larger than the groundmass, in which case the texture is known as porphyritic. A granitic rock with a porphyritic...

 outcrops along with smaller dolerite areas, the tops of hills are capped with laterite

Laterite

Laterites are soil types rich in iron and aluminium, formed in hot and wet tropical areas. Nearly all laterites are rusty-red because of iron oxides. They develop by intensive and long-lasting weathering of the underlying parent rock...

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