Hakata-yu

405. Hakata-yu, Futsukaichi Onsen, Fukuoka Onsen for 350-450. According to their website, they're very proud of their history — the business started in 1860, and the history of Futsukaichi Onsen goes back over 1,300 years. Operating hours stated as 10:00 to 21:30. They stamp the 88 Onsen of Kyushu book. Bath photo from the internet matches reality. I visited on a Sunday evening. There were so many people wanting to bathe that at reception they offered to give me a ticket for entry one hour later. I counter-offered to get one three hours later, so I'd have time to go grab dinner at a ryokan. The staff is young but very pleasant and attentive — they handle the visitor load well. Inside there's a bath with clear water, temperature 41-42. Breathing inside is fine.