Melbourne, Australia

Game on: It isn't just the size of Melbourne's Crown Casino (the largest in Australia) that gives it an edge. Every January, it brings in some serious high-stakes action with the Aussie Millions (American Erik Seidel scooped up AUD$2.5 million when he won the $250,000 Super High Roller event in 2011, the biggest buy-in in poker history). The Aussie Millions also coincides with the Australian Open held at Melbourne Park—convenient for sports bettors, of which Melbourne has plenty. In fact, the first Tuesday of November is a public holiday called Cup Day in honor of the Melbourne Cup held at Flemington Racecourse. Billed as "the race that stops a nation," the horse-racing contest draws more than 100,000 people every year, many in fancy dress.

Inside bet: In addition to clubs, bars, restaurants, and shops, the casino complex houses the 482-room Crown Towers hotel. So you won't have to carry all those winnings very far.

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