Aoyama-dori intersects with Omote-sando and down this street was a building I was interested in seeing. Along the way, I ran into this curious sculpture that you've seen before. It's by Taro Okamoto, 1985.
I learned that it's in front of the National Children's Castle (Kodomo no Shiro) that is now closed after 30 years. It was a multi-story play space and learning center where kids could play in the big city.
Omote-sando & Aoyama-dori