みなと温泉 波葉の湯

Minato Onsen Namiha-no-yu at Bayside Place Hakata draws a natural hot spring from 800 m underground and bills itself as the only day-bathing spot in Fukuoka City with a free-flowing open-air spring bath. Each side has a high-temperature sauna, the men's set near 100 °C, and a 16 °C cold bath. A jjimjilbang-style stone spa adds seven sauna rooms, including a 95 °C lie-down room with Aufguss sessions. The stone spa, bathing included, costs ¥1,780 on weekdays; baths open 10:00 to 23:00.

Monday to Sunday: 10:00 AM – 11:00 PM