Fodor's Expert Review Yunomori Onsen & Spa
Sukhumvit
Spa
Bangkok's first Japanese-style onsen (hot springs) uses real spring water---thousands of gallons of it---trucked up from the famed Raksa Warin Hot Springs in Ranong. You can immerse yourself in pools of different temperatures, from a toasty hot tub down to a cold plunge pool. There are first-class spa treatments, too.