This huge sculpture made from steel and concrete stands in the middle of the Milly forest, in the Île-de-France region. It was created almost in secret in 1969 by Jean Tinguely, Niki de Saint-Phalle and other artists. Decorated with mirrors and cogwheels, the huge 22.5m-high head is further embellished with a pool of water that reflects the blue of the sky. Inside its strange labyrinth are works by artists close to Tinguely such as César, Giovanni Podesta, Larry Rivers etc.