While organizers often promise the Olympic Games will bring an economic boom, citizens and governments can be left with big debts.
Greece spent lavishly on the 2004 Athens Games, with final budgets landing billions of dollars in the red.
According to a working paper by researchers at Oxford's Saïd Business School, the project went over budget by 60%.
Greece also built too many hotel rooms and fell victim to hopes that the Olympics would lead to longer-term gains thanks to tourism.
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Many of the stadiums built for the Olympics, like the one shown here, now sit unused.