Nakagin Capsule Tower

Metabolism proposed that a building should behave like an organism, with a durable frame and parts replaced as they wear out. Nakagin was the world's first built example of capsule architecture. Each capsule was an all-welded steel box of 2.5 by 2.5 by 4 metres — the dimensions, Kurokawa noted, of a traditional tea room — fitted out in a factory that also made shipping containers, trucked to Ginza and bolted to a core with four fasteners so that any one could be swapped without touching its neighbours. A single round window, 1.3 metres across, faced the street. The system was never exercised: no replacement capsule was ever manufactured and none was ever changed. The building fell into disrepair, fundraising and landmark campaigns failed, and it was demolished in 2022 after half a century. Twenty-three capsules were saved.