The tide of Japanese onsen sweeping Bangkok continues with The One Sand Bath Therapy, a new spa offering hot sand tubs which use volcanic Japanese sand selected for its larger than average grains.

The spa claims that the 50 essential vitamins and minerals contained within this sand will improve your immune system, stave off signs of aging, detoxify your system and improve blood circulation. 

Prices start from B2,500 (soft opening rate at B1,500 until further notice) for a one-hour session of sand bathing (15 minutes sand bath followed by a scrub and shower).

The therapist will check your pulse before bathing to analyse the proper duration your body can handle. While the experience is super-relaxing, you should be prepared to sweat... a lot. The default temperature for the tub is 55 degrees Celsius, and you shouldn't reall stay longer than 20 minutes. In fact, the owners compare it to rigorously excercising for one-and-a-half-hours.

Aside from the sand onsen, the spa also offers aromatherapy (from B800/60 mins) and Thai massage (from B500/60 mins). 

See also: Bangkok's best spots for a Japanese onsen experience