Mount Tilga is a hill

Hill

A hill is a landform that extends above the surrounding terrain. Hills often have a distinct summit, although in areas with scarp/dip topography a hill may refer to a particular section of flat terrain without a massive summit A hill is a landform that extends above the surrounding terrain. Hills...

 329 metres high which rises sharply out of the plain eight kilometres north of Condobolin

Condobolin, New South Wales

Condobolin is a town in the west of the Central West region of New South Wales, Australia, on the Lachlan River. At the 2006 census, Condobolin had a population of 2,847.- History :...

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Mount Tilga is said to be the exact centre of New South Wales

New South Wales

New South Wales is a state of :Australia, located in the east of the country. It is bordered by Queensland, Victoria and South Australia to the north, south and west respectively. To the east, the state is bordered by the Tasman Sea, which forms part of the Pacific Ocean. New South Wales...

., but establishing the centre of an irregular shape

Centroid

In geometry, the centroid, geometric center, or barycenter of a plane figure or two-dimensional shape X is the intersection of all straight lines that divide X into two parts of equal moment about the line. Informally, it is the "average" of all points of X...

 is not a straightforward matter. Just where the centre of the State lies is open to dispute.

According to Geoscience Australia

Geoscience Australia

Geoscience Australia is an agency of the Australian federal government. It carries out geoscientific research.On a user pays basis it produces geospatial products such as topographic maps and satellite imagery.-History:...

, which has investigated the issue, a possible centre for New South Wales is just off Cockies Road, 33 km west-north-west of Tottenham

Tottenham, New South Wales

Tottenham is a small town in Lachlan Shire in the Central West of New South Wales, Australia. It had a population of 343 in 2006, including 21 indigenous people and 20 foreign born people ....

, a small town 110 kilometres west of Dubbo. This spot, (32°09′48"S 147°01′00"E) south of the Fiveways Intersection, is marked by a cairn constructed for Australia's Bicentennial celebrations

Australian Bicentenary

The bicentenary of Australia was celebrated in 1970 on the 200th anniversary of Captain James Cook landing and claiming the land, and again in 1988 to celebrate 200 years of permanent European settlement.-1970:...

 in 1988

1988 in Australia

-Incumbents:*Monarch – Elizabeth II*Governor-General – Sir Ninian Stephen*Prime Minister – Bob Hawke-Premiers and Chief Ministers:*Premier of New South Wales – Barrie Unsworth , then Nick Greiner*Premier of Queensland – Mike Ahern...

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