A traveller's dream trip to the land Down Under quickly turned into an absolute blunder when he realised he'd booked a flight to Sidney, USA instead of Sydney, Australia. 

New Yorker Kingsley Burnett was hoping to escape the state's freezing winter and instead spend time lounging on one of Sydney's many sunny beaches, perhaps pat a kangaroo and join a cruise from Circular Quay.

But Mr Burnett quickly realised he'd made a grave mistake when his flight was far shorter than expected and he couldn't see beaches, the Harbour Bridge or the Opera House.

'I saw a mountaintop covered in white snow. At that point, I knew I was in trouble,' Mr Burnett, 62, told local TV station KTVQ. 

He had booked and caught a flight to the town of Sidney in the US state of Montana - population 6,346 - rather than the Australian city of Sydney - population 5.3million. 

'It's a matter of acronyms. The S-Y-D as opposed to S-D-Y. Somebody has to fix that,' Mr Burnett said.

He was referring to the codes used by the respective airports that led to the error which saw him land in Billings, Montana to board a connecting flight to Sidney. 

If you're wondering how he didn't notice the enormous price difference, Mr Burnett was travelling on a tight budget and had been happy to find a bargain basement ticket for what he thought was a flight to the other side of the planet.

There was now no way the New Yorker was going to make it to Sydney for his cruise, so he stayed in the local Boothill Inn while he waited for a flight home.

Shockingly, the manager Shelli Mann said the Sydney/Sidney mix-up had happened before.

'This is the second time we've had a guest that was trying to get to Sydney, Australia,' she said.

Mr Burnett was very grateful to Carol Castellano of American Airlines who helped him get a flight back to New York.

'Montana didn't have kangaroos. It had Carol. And that was good enough for me,' he said. 

There is also a Sydney - spelt the same way as its more famous namesake - in Nova Scotia, Canada.

In March, 2017 Dutch teenager Milan Schipper ended up on the east coast of Canada rather than the east coast of Australia. 

When he was booking the flight, the then 18-year-old found one ticket that was almost $300 cheaper than the rest.

'So I thought, "Well, let's book that one,"' he told the Canadian Broadcasting Corporation at the time.

He first realised something was wrong when he landed in Toronto for a stopover and saw the Air Canada plane that would take him to Sydney.

'The plane was really small and so I figured, would that make it to Australia?' he said.

He boarded anyway, then he saw the map on the screen on the seat in front of him.

'I saw the flight plan was going to go right, not left. It was about the time that I realised there was another Sydney,' he said.

Mr Schipper was far from alone. An American woman on the same flight as him had made the same error, he said.

In 2002, two British teenagers ended up in Sydney, Nova Scotia while trying to get to Australia, as did an Argentinian tourist in 2008, a Dutch man and his grandson in 2009 and an Italian couple in 2010.

There is also a Sydney Parade in Dublin, Ireland. It has a cricket ground and a train station, but no airport, so there have been no reported attempts of people mixing it up with Sydney, Australia, Sydney, Canada or Sidney, America.

Not yet, anyway.