01Workshop
Hands-on cooking and tasting classes where we learn to use herbs by actually working with them. Sauna events also include bathing in the steam of simmered herbs.
Japan Root Herb AssociationJRHA
A registered trademark advocated by the Japan Root Herb Association (JRHA), it organizes the roots long valued in traditional and folk medicine (ginger, turmeric, galangal, etc.) — in contrast to aroma-led green herbs.
Founded May 2024・Tokyo・Corporate number 5011105011042

A nationwide index of the facilities whose permanent use of herbs in the sauna could be confirmed in primary sources such as their official site. Yakuso (medicinal herb) steam, Thai-style herbal steam, herbal löyly and vihta are distinguished as styles. Search by prefecture and by scent.
Open the guide→Only facilities whose permanent use of herbs in the sauna could be confirmed on their official site or an equally citable source are listed; the date of verification is given on each facility page. Prices, opening hours and the herbs used are subject to change.
20 herbs in three groups — roots, green herbs, and the herbs of Japan. Each entry carries its species, family, part used, aroma and Thai name, and how it has been handed down in Thai traditional medicine.
Roots & rhizomes — 6
Leaves & fruit — 5
Herbs from Japan — 9
Ginger
Zingiber officinale
Zingiberaceae

Plate: drawn after the rhizome figure in Köhler’s Medizinal-Pflanzen (1887)
Workshops, the Root Herbalist certification, and on-site training in Thai traditional medicine — the three paths of study offered by JRHA.
01Hands-on cooking and tasting classes where we learn to use herbs by actually working with them. Sauna events also include bathing in the steam of simmered herbs.
02Study Thai traditional medicine and gain professional knowledge of root herbs. Learn history, theory, herbal sauna, oils, and drinks.
03An on-site herb school and facility study programme. In Phuket we visit island sauna houses; in Bangkok we see herbal markets and historic sauna sites.
The programme starts and ends in Thailand; flights and overseas travel insurance are arranged by each participant. The fee covers local transport, accommodation, facility visits, sauna sessions and the course and certificate. Meals, flights and travel within Bangkok are not included.
Programme details and application→Membership applications are accepted year-round. The membership year runs from April 1 to March 31 of the following year.
The Japan Root Herb Association welcomes everyone who wishes to support the development of RootHerb® in Japan.
Joining takes two steps: submit the registration form and transfer the annual dues. Once we confirm receipt, we notify you of your membership number by email.
Hachijo Terrace sauna & retreat on Hachijojima (Tokyo) — a retreat with a Finnish sauna, open-air bath and lodging. A Thai-style herbal sauna, supervised by the Japan Root Herb Association, is planned for 2027.
Hachijo Terrace official site→Use the contact form for questions about courses, certification and on-site training, for press and publication enquiries, and to submit information for the sauna guide. Questions about how facilities are selected for the guide are welcome there too.
Instagram @jrha_official — you can also reach us by direct message.
Japan Root Herb Association・Founded May 2024・Tokyo・Corporate number 5011105011042・Representative director: Satoshi Ryuto