The townsite of Onslow is located on the coast of the Pilbara region of Western Australia, 1386 kilometres north of Perth. Created as a port townsite in 1885 to service the pastoral industry of the Ashburton and Yannarie River districts, the original Onslow was situated at the mouth of the Ashburton River. It is named after Sir Alexander Campbell Onslow K.B., Attorney General of Western Australia at the time.
The jetty at the original Onslow Townsite was very primitive. At low tide only vessels drawing a loaded depth of 12ft could berth and the regular coastal steamers had to anchor out in the Roads. In 1922 it was decided to establish a new deep water jetty 15 kilometres to the northeast at Beadon Point. At first it was felt Onslow could stay where it was, and be connected to the jetty by a tramway, but this was not practical, and there was considerable pressure to move the townsite. Lots were surveyed at Beadon Point in 1923, and Onslow landowners sought to be relocated in the new townsite. When the new townsite was gazetted on 10 January 1924 it was named "Beadon", but just two weeks later was renamed as part of Onslow. Most of the town moved in 1925 and the original Onslow townsite was later cancelled.