In 1922 an agreement was signed between the prime minister
Billy Hughes, the acting premier for South Australia,
John George Bice, and the premier of Western Australia,
James Mitchell to set the border along the
129th meridian east longitude and defined the boundary by lines drawn north and south through the centre of the Deakin Obelisk, erected in 1926 near
Deakin, Western Australia and the Kimberley Obelisk, erected in 1927, near
Argyle Downs, in the
Kimberley Region of Western Australia. The site is not named after a single Surveyor-General, because there were a number of them present as follows. ==Access==