While in Hakone, Japan, we also visited the Hakone Open-Air Museum. In our opinion, the two most amazing pieces in the collection were both play environments for children. Children are free to play in these structures. The photos above are of a piece created by Toshiko Horiuchi MacAdam in 2009 called "Knitted Wonder Space 2"
The other piece that we really liked was another children's play environment created in 1994 by Peter Pierce called "Curved Space Diamond Structure"
Steel Vessels by Tony Cragg
Alexander Calder
Naum Gabo