Located in Japan’s Gumma Prefecture, this square museum is dedicated to the native poet and illustrator Tomihiro Hoshino.
The building is composed of a collection of cylinders within a 52m square. Since the museum is made up of a group of tightly packed circular rooms, like a cluster of soap bubbles, it was necessary to make the walls as light as possible. A lightweight steel framework was used for the structure of the walls and roof.
Three of the 33 cylindrical rooms have a reinforced concrete structure and the rest are of 9mm-thick steel plate. The roof is composed of assemblies of steel fan-shaped pieces.
The cylinders make up a highly efficient structural system, supporting each other and distributing forces around the building.