Where is the centre of Australia?

Geoscience Australia lists five possible 'centres' based only on the Australian mainland. Picture Shutterstock

While this might sound like a simple question, the answer is a mess of possible options, plus sub-variants. It depends on what what "centre" means, and "of where".

Unlike a regular shape such as a circle or a square, Australia (or almost any land area) is an untidy tangle of bays, inlets, peninsulas and islands.