In Tokyo the public transportation stops around midnight(no idea why!)
and all the people that life in the outskirts and want to go drink after work(which are a lot) cannot reach their homes in the evening.
Since all hotels are kinda expensive, there was a big need for a lot of cheap accomodation, so they started to open capsule hotels,
which are a lot of small cabins in a small place which reminded us of sleepers in trains of ships...

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