Yunomori onsen & spa
Time Out says
Why bother flying to Japan when Yunomori onsen & spa is the first authentic one that made it to Bangkok.
Yunomori onsen & spa boasts a Japanese garden and sources the mineral water all the way from the thermal springs of Wat Wangkanai in Ranong province, Southern Thailand to its onsen. Other facilities are also available including Japanese baths, sauna, steams and showers.