China has the Great Wall, France the Notre Dame Cathedral and Egypt the pyramids. Australia's contribution to the world's wanderlust is less lofty.

Our top three tourist attractions are casinos, apparently, drawing more luckless losers from abroad than the Sydney Opera House.

A list of the world's top 100 tourist attractions marks Crown Casino as Australia's most popular destination, with 10.9 million people visiting the Melbourne ''integrated resort'' in 2010.

No wonder Crown recently relied on the flattering Euromonitor International report on visitor numbers as part of its successful tilt at a second Sydney casino.

Just behind Crown for tourists Down Under is the Gold Coast's Jupiters casino (10.6 million visitors) and the Star in Sydney (9 million). The Opera House attracts a piddling 7.4 million by comparison.

The visitor tallies have been unchallenged to date - and repeated ad nauseam by the good folk at Australia's gambling dens. But anti-gambling campaigner Tim Costello smells a rat.

''I think there's a bit of a fiddle in these figures,'' he said.

Indeed, Euromonitor, an independent market researcher, admits ''measuring visitor numbers to casinos is notoriously difficult''. Its list has a curious preponderance of casinos and children's theme parks.

The Great Wall of China was ranked first overall with 19.8 million visitors, followed by three Disney theme parks. Britain's greatest attraction was apparently not Stonehenge, the Tower of London or Buckingham Palace but a family fun park in Milton Keynes.

A spokesman for Australia's Tourism & Transport Forum, Rowan Barker, declined to dispute the visitor figures but suggested the Opera House had been short-changed.

''We know that people come to Sydney to see the Opera House,'' he said. ''There is no doubt it is an international drawcard.''

But this hand of cards appears to favour Crown.

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