The Pilbara (pronounced as "Pillbra") is a large, dry, thinly populated region in the north of Western Australia known for its vast mineral deposits, in particular iron ore. It is one of nine regions of the Regional Development Commissions Act 1993, and is also a bioregion under the Interim Biogeographic Regionalisation for Australia (IBRA).
The WA Gas Industry  claims that the region takes its name from pilbarra, an Aboriginal word for the mullet and that the name was derived from the Pilbara Goldfield, discovered in 1885, which was itself named after Pilbara Creek (originally spelt "Pilbarra") a tributary of the Yule River.
Alternatively, Wangka Maya (Pilbara Aboriginal Language Centre) says in its publication Bilybara (p. ii) that it derives from the name for the Pilbara region in Nyamal and Banyjima, bilybara meaning 'dry'.
The Pilbara region covers an area of 507,896 km² (including offshore islands). It has a population of just under 40,000 people, most of whom live in the western third of the region, in towns such as Port Hedland, Karratha, Wickham, Newman and Marble Bar. A substantial number of people also work in the region on a fly-in/fly-out basis.
The Pilbara consists of three distinct geographic areas. The western third is the Roebourne coastal sandplain, which supports most of the region's population in towns and much of its industry and commerce. The eastern third is almost entirely desert, and is sparsely populated by a small number of Aboriginal peoples. These are separated by the inland uplands of the Pilbara Craton, including the predominant Hamersley Range which has a considerable number of mining towns, the Chichester Range and others. These uplands have a number of gorges and other natural attractions. Pilbara contains some of the world's oldest surface rocks, including the ancient fossilised remains known as stromatolites and rocks such as granites that are more than three billion years old.
The climate of the Pilbara is semi-arid and arid, with high temperatures and low irregular rainfall that follows the summer cyclones. During the summer months, maximum temperatures exceed 32°C (90°F) almost every day, and temperatures in excess of 45°C (113°F) are not uncommon. The Pilbara town of Marble Bar set a world record of most consecutive days of maximum temperatures of 100 degrees Fahrenheit (37.8 degrees Celsius) or more, during a period of 160 such days from 31 October 1923 to 7 April 1924.
Flooding is a major hazard in the Pilbara with periods of torrential rainfall between November and May. Like most of the north coast of Australia the coastal areas of the Pilbara experience frequent tropical cyclones. Due to the relatively low population density in the Pilbara region cyclones rarely cause large scale destruction or loss of life.
Most of Australia's iron ore is mined in the Pilbara, with mines mostly centred around Tom Price and Newman. The iron ore industry employs 9000 people from the Pilbara area. The Pilbara also has one of the world's major manganese mines, Woodie Woodie, situated southeast of Port Hedland.
Iron ore reserves were first discovered by Lang Hancock, and considerable portions of the Pilbara region are still claimed by his daughter Gina Rinehart and the family company Hancock Prospecting continues to gain from its interests in the region - as well as commencing its own mine workings. Blue asbestos was first mined in Wittenoom Gorge in 1943.
Geoscience Australia calculates that the country's "economic demonstrated resources" of iron currently amount to 24 gigatonnes, or 24 billion tonnes. It is being used up at a current rate of 324 million tonnes a year. In the 1960's it was reportedly called "one of the most massive ore bodies in the world" by Thomas Price, then vice president of US-based steel company Kaiser Steel.
According to the Australian Bureau of Agricultural and Resource Economics, that resource is being used up at a rate of 324 million tonnes a year, with rates expected to increase over coming years. Experts Dr Gavin Mudd (Monash University) and Jonathon Law (CSIRO) expect it to be gone within 30 to 50 years (Mudd) and 56 years (Law).
The region also has a number of sheep-grazing stations and a substantial tourist sector, with popular natural attractions including the Karijini and Millstream-Chichester national parks, the Dampier Archipelago and the Ningaloo Reef.
The currently (2010) active iron ore mines in the Pilbara are:
Currently four heavy-duty railways are associated with the various iron-ore mines, with a fifth line proposed to serve the Fortescue Metals Group Ltd. mines. The railways are all standard gauge and are built to the heaviest North American standards. Between 2008 and 2012, Rio Tinto proposes to convert to driverless trains on its railways. An additional 300km line is planned from the Roy Hill mine to a port at Boondarie, near Port Hedland.
The ports of the Pilbara are:
The dominant flora of the Pilbara is acacia trees and shrubs and drought-resistant Triodia spinifex grasses. Several species of acacia (wattle) trees are endemic to the Pilbara and are the focus of conservation programs along with wildflowers and other local specialities.
The Pilbara is home to a wide variety of endemic species adapted to this tough environment, including dozens of species of stygofauna; microscopic invertebrates which live underground in the aquifers of the region. The Pilbara olive python, the Western Pebble-mound Mouse, and the Pilbara Ningaui of the Hamersley Range are among the many species of animals within the fragile ecosystems of this desert ecoregion. Birds include the Australian Hobby, Nankeen kestrel, Spotted Harrier, Mulga Parrot, budgerigars, and Sulphur-crested Cockatoos.
Wildlife has been damaged by the extraction of iron, natural gas and asbestos but the protection of culturally and environmentally sensitive areas of the Pilbara is now advanced by the delineation of several protected areas including the Millstream-Chichester and the Karijini National Parks.