Australia has one of the highest number of micro-nations in the world, with citizens choosing to establish their own rule and shrug off the shackles of the country's constitutional democracy.

The country's longest-running and arguably most successful micro-nation recently transitioned its rule.

But while going your own way (tax-free, anyone?) may sound appealing, a senior legal authority warns would-be monarchs may face significant legal barriers.

Murdoch University constitutional and international law specialist Lorraine Finlay said while legally Australia does not recognise the many and varied micro-nations within its borders, the relationship was not generally antagonistic.

"The approach of the Australian Government tends to be a very practical one, that whilst legally it doesn't recognise them as separate nations, practically they're often allowed to exist," she said.

Some micro-nations boast their own postal services and facilities. ( ABC News: Eliza Borrello )

Ms Finlay said for anyone looking to set up their own fiefdom, the Montevideo Convention on the Rights and Duties of States set out the classic criteria for statehood that is recognised at an international level, including:

A permanent population

A permanent population A defined territory

A defined territory A government exercising control over that territory

A government exercising control over that territory A capacity to enter into relations with other states

"If other states aren't going to recognise you, it's incredibly difficult at the international level to actually become a legitimate nation," Ms Finlay said.

The Australian Constitution talks about an indissoluble federation, and does not have provisions for secession, which did not stop Western Australia attempting to do so in 1933, where the majority of the state voted to leave the Commonwealth in a referendum.

Ms Finlay said that despite that, at an international level, there was recognition of secessionist movements.

While micro-nations set out their own internal system of law, Australian law does apply in those territories, and it then becomes a question of enforcement.

"My guess would be that if there was a serious enough crime committed in any of those micro-nations, I would assume that our authorities would have no hesitation in going in and enforcing Australian law," Ms Finlay said.

So who are the Australian micro-states?

Empire of Atlantium

The Empire of Atlantium covers 0.76 square kilometres on farmland near Boorowa in southern NSW. ( Supplied: Empire of Atlantium )

Claiming to be the smallest micro-nation in Australia, the rural New South Wales idyll of Atlantium was founded in 1981 by leader George Cruickshank, who also goes by "Imperial Majesty George the second, emperor and first among equals".

The property boasts its own pyramid, as well as a post office, government buildings, currency and national anthem, and claims to be entirely independent of the Australian power, gas and water grids. You can even stay there at a property listed on Airbnb for a modest sum.

Much like the Aerican Empire, it ultimately wants a world where it doesn't need to exist, being a proponent of global governance.

Aerican Empire

More thought experiment than sovereign nation, it was founded by a Montreal-based psychiatrist and claims one-square kilometre of territory in Australia, as well as Montreal, other seemingly unconnected parts of earth, Mars, Pluto and an imaginary planet.

While still firmly tongue-in-cheek, it has evolved and at times has claimed hundreds of nominal citizens. A self-described democratic socialist society, according to its mission statement, "The Empire exists to facilitate the evolution of a society wherein the Empire itself is no longer necessary".

Grand Duchy of Avram

If Tasmania is not disconnected enough from the mainland, you can head to Avram, founded in the early 1980s by John Charlton Rudge.

Mainly operating as a national bank, it moved from George Town to Strahan, in Tasmania's west. It reportedly issues its own bank notes, for which Australian dollars can be exchanged.

Mr Rudge, known as His Grace the Most Noble Duke of Avram, sat in the Tasmanian Parliament for a single term from 1989 to 1992.

Principality of Hutt River

Prince Leonard says it will be a mental relief once he has abdicated to his son, Prince George. ( ABC News: Eliza Borrello )

The longest-running micro-nation in Australia declared itself an independent state in 1970, with Prince Leonard claiming to rule over 75 square kilometres in the WA's Mid West.

The split from Australia was reportedly prompted by a dispute over wheat production quotas, which were tightly controlled by the Australian Wheat Board.

The principality is a tourist attraction and issues its own stamps and currency. It also has its own passports.

Gay and lesbian kingdom of the Coral Sea Islands

Founded in 2004, basically does what it says on the packet.

Protestors angry that the Federal Government would not acknowledge same-sex marriage, it claims territory over a group of uninhabited islets east of the Great Barrier Reef spread over a vast area.

They fly the rainbow flag, and have a declaration of independence that riffs on its US counterpart, recognising people as created equal, but also decries homophobia and discrimination: "In countries where we have lived for centuries, we are still cried down as strangers ... in the world as it is now and for an indefinite period ... I think we shall not be left in peace".

Murrawarri Republic

The brown on the Murrawarri Republic flag represents mother earth, while the blue represents the sky where spirits reside until their return on the falling star. ( Wikicommons: Muffin Wizard )

An Aboriginal micro-nation that declared independence in 2013, founders demanded a treaty between the Murrawarri nation and the Crown of Great Britain, a deed of secession, and a document acknowledging a declaration of war against the Murrawarri Nation and its people by Great Britain.

They claim a land area spanning across parts of Queensland and New South Wales.

Yidindji Tribal Nation

An Indigenous Australian micro-nation established across an area south of Port Douglas, through Cairns, inland across the Atherton tablelands, and 80km out to sea.

It is led by activist and former journalist Murrumu Walubara Yidindji, and the nation hopes to enter into a memorandum of understanding with Australia.

Mr Murrumu has been arrested, according to reports, for using license plates issued by the micro-nation. He has relinquished his passport, bank accounts and Australian citizenship.

Principality of Wy

Paul Delprat describes himself as an 'exiled Prince'. ( Supplied: Principaliy of Wy )

A suburban territory established after a stoush between a Sydney man and his local council, over a bid to build a driveway over their frontage.

Headed by Prince Paul Delprat, the principality claims to have seceded in 2004, after an 11-year fight with the council to build the driveway to their property.

A ceremony was apparently held at the Mosman Town Hall.

Special mention: Aboriginal Provisional Government

The APG maintains Aboriginal people have always been a sovereign people. ( Supplied: Aboriginal Provisional Government )

The APG, founded in 1990, argues Aboriginal people have always been sovereign.

While it makes no formal claim to land, so failing the nation state test, you could arguably just stand anywhere in Australia to knock on its doors.

The Government issues passports and recognises citizens.