Were you a bit fooled by French artist François Abélanet's grassy 3-D anamorphosis optical illusion? If so, admit it. "Qui Croire?" which means "Who to believe?" is a sprawling mass of grass of sand that appears when viewed at the proper angle as though it were a large sphere. The amazing optical illusion is 100 meters long and takes up 1200 square meters of lawn. It is covered in 300 square meters of sedum and 90 people worked on it for five continuous days to give it this effect. The public will be able to visit this mind-bending land art project at Paris City Hall until 15 July, 2011.
Abélanet states: 'we live in a world where one hears the debates of ecologists, scientists, manufacturers... I simply wanted to note the problem of the tree and invite people to question the place that it, nature, and the environment have in their lives.'

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