By the Meiji Restoration in 1868 there were 600 such sento in Tokyo alone.

ECONOMIST: The Japanese are a super-clean lot. Obsessively so?

And the bathing facilities are clean, although some travellers make the pilgrimage to the local sento (Japanese public bath) for a soak.

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Although such sinful baths were the exception, bureaucrats of the time fretted that sento posed a threat to public morality.

ECONOMIST: The Japanese are a super-clean lot. Obsessively so?

The zenith of the sento was in the 1960s, when there were over 23, 000 scattered over Japan and 2, 700 in Tokyo.

ECONOMIST: The Japanese are a super-clean lot. Obsessively so?

If you can go six rounds with Sento you can earn maybe 1, 200 euros - enough to live on for a month.

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Depending on whom you believe, the first commercial baths or sento (penny baths) were opened either in 1590 in Osaka or 1591 in Edo (now Tokyo).

ECONOMIST: The Japanese are a super-clean lot. Obsessively so?

But Sento is no ordinary fighter.

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