The Centre(s) of Australia


When Natmap in conjunction with the Royal Australian Survey Corps (RA Survey) and the States completed the field work for the Geodetic Survey of Australia in 1965, the last thing on anyone’s mind was that their work would enable the finding of the centre of Australia.


The Geoscience Australia website provides some of the early writings on the subject as well as the science behind the various methods used.


Historically, however, early explorers had tried to reach the centre of the continent. On his final exploration expedition (1844-46), Captain Charles Napier Sturt led a party from Adelaide in an unsuccessful attempt to reach the centre of Australia.  He was unable to get through or around the Simpson Desert. John McDouall Stuart was a member of that party and later led several expeditions in his own right. In April 1860, on his fourth expedition, Stuart calculated by survey observations that he had reached the centre of the continent at a point about 210 km north of Alice Springs. Stuart named a nearby feature Central Mount Sturt after his former leader. The name was later changed to Central Mount Stuart. This feature is a few kilometres west of the Stuart Highway about 17 km north of the Ti Tree Roadhouse; there is a monument to Stuart beside the highway nearby.


The first “calculated centre” was determined using 275 Australia-wide astronomic/geodetic comparisons. This point became the origin for the adjustment of 2506 geodetic stations and the basis for the Australian Geodetic Datum, 1966 (AGD66). In recognition of the first Director of National Mapping and chair of the National Mapping Council as well as Commonwealth Surveyor-General, Frederick M Johnston, this point was named the Johnston Geodetic Station.


The Johnston Geodetic Station is on a rocky outcrop on Mt Cavenagh Station, NT south of Kulgera. The monument was specially built by Natmap in 1965 and contains a descriptive plaque.


In the 1980s as mapping information became available digitally the database of geographical points could be interrogated. The geographical co-ordinates for the centre of gravity, the furthest point from the coastline and median point were extracted to the nearest minute of arc (accuracy ±1km). The methods of calculation are outlined in this 1988 article.


The geographical co-ordinates for the Lambert gravitational centre were determined in 1988, as a Bicentennial project. Named in honour of Dr. Bruce P Lambert, a former Director of National Mapping, for his achievements in the national survey, levelling and mapping of the continent, it is the only other “centre” to be monumented. The Lambert gravitational centre is some distance off the road between Finke and Kulgera, NT. More detail may be found in the Royal Geographical Society of Queensland paper the Lambert Centre Project.


The following table summarises the five “centres” and their co-ordinates after which are relevant photos and detailed maps.



Latitude (S)

Longitude (E)

Johnston Geodetic Station

25º 56’ 49.3”

133º 12’ 34.7”

Lambert gravitational centre

25º 36’ 36.4”

134º 21’ 17.3”

Centre of gravity

23º 07’

132º 08’

Furthest point from the coastline

23º 02’

132º 10’

Median point

24º 15’

133º 25’


Map showing the geographical locations of the five “centres”.


Map showing the geographical location of the Johnston Geodetic Station on Mt Cavenagh, NT (note the station is situated on Private Property).



Inscription on the plaque of the Johnston Geodetic Station and the station monument under construction in November 1965 (courtesy Ed Burke).


Map showing the geographical location of the median point.


Map showing the geographical location of the centre of gravity and furthest point from the coastline.


Map showing the geographical location of the Lambert Gravitational Centre.



Lambert Gravitational Centre monument and inscription on the plaque (courtesy Ed Burke).

Note that the dates on the plaque are wrong (1912-1992 should be 1912 – 1990) as documented at:


















Johnston Geodetic Station and the Lambert Gravitational Centre August 2012 (courtesy Laurie McLean).



by Paul Wise 2012 updated 2013 with assistance from Laurie McLean