Academic website The Conversation has a report on the Australian local government councils.
“The 565 councils in Australia range greatly in size. The largest, Brisbane City Council in Queensland, has an annual operating budget of A$2.9 billion and serves a community of just over a million people. It covers an area of 133,809 hectares.
The smallest, Sandstone Shire Council in Western Australia, comprises a population of 116 and covers a land area of 3,266,650 ha. This is comparable to the size of Belgium. It had an annual operating budget in 2014 of $3.4 million.”