An anamorphosis is used to show something that is only recognizable from a certain location and in a certain angle. Most of them are classically hidden inside paintings. But a city decided to use one anamorphosis to make car drivers believe that there is a child playing on the road, forcing them to slow down… where children may play and be at risk from speeding cars.
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It would have been even better in open air. But this one is already quite nice.
Source: Geekosystem.