Multi-Story Used Wood Seaside Treehouse

Belgian designer Jean Paul Lespagnard built this tree house in collaboration with American artist Ethan Hayes-Chute at the Villa Noailles in Hyères, on the Mediterranean coast of France.
http://www.ethanhc.com/3d/048.htm
Photo by Ethan Hayes-Chute
Thanks to Peter Robinson and Peaspeculiars (see comments below)for tracking this down.