The Italian motor dates back to 1921 and only 52 were ever built. Of those this is the only one that survives to this day. 

The 1921 Alfa G1 spent much of its life in Australia after it was exported there soon after being made.

A vintage Alfa Romeo (pictured in side profile) built in 1921 that was hidden on a farm in the Australian Outback for decades has gone on for sale and for an eye-watering £750,000

The Alfa Romeo G1 dates back to 1921 and only 52 were ever built. Of those, this is the only one which survives

A stunning black and white photo taken in the 1920s shows the car's original Australian owner

With the Italian economy struggling in the wake of the First World War, Alfa decided to send all of their new G1s down under in the hope of making the most from each sale.

Even then he refused to give up the Alfa, hiding it from officials on a farm in the Queensland Outback.

Alfa enthusiast Ross Flewell-Smith began an extensive 10 year restoration project which included crafting a new Torpedo-style body on to the original chassis.

The car left Australia in 2012 after it was purchased by an American collector, who again gave the car an extensive restoration.

Jeremy Clarkson has always insisted Alfa Romeo's have a charm all of their own making the G1 a must-have for serious motoring enthusiasts

The 1921 Alfa G1 spent much of its life in Australia after it was exported there soon after it was made

With the Italian economy struggling in the wake of the First World War, Alfa had decided to send all of their new G1s down under in the hope of making the most from each sale

Now, after owning the Alfa for six years, he has decided to sell the G1 at RM Sotheby's Auctions in Arizona, US.

The vintage motor belies the brand's notorious reputation of being unreliable.

Famously, Jeremy Clarkson maintains that no one can call themselves a true petrolhead until they have owned an Alfa.

Its first owner went bankrupts but hid the car away in the Queensland Outback hoping officials would not find it

Alfa enthusiast Ross Flewell-Smith purchased the car 25 years later and began an extensive 10 year restoration project which included crafting a new Torpedo-style body on to the original chassis

A spokesman for RM Sotheby's, said: 'This exciting, powerful and oldest-known surviving Alfa Romeo presents a rare opportunity for the discerning automotive connoisseur to own a historic machine.

'It is a car that will be a welcome entrant at vintage rally events where it will certainly be the centre of attention, as well as an absolute blast to drive.

'We expect it to fetch in the realm of $1,000,000, which is around £750,000.'

The sale takes place on January 18. 

A spokesman for RM Sotheby's said: 'We expect it to fetch in the realm of $1,000,000, which is around £750,000'