Japan’s more than 25,000 naturally-occurring mineral hot springs help power 3,000 spa resorts across the country.

Thanks to its location in a volcanic zone, Japan is a hotbed -- quite literally -- of geothermal activity. There are more than 25,000 naturally-occurring mineral hot springs which help power 3,000 spa resorts across the country.

The area around Kyoto, Japan’s former imperial capital, is home to more than a dozen hot springs, called onsen. One of the most popular is Kurama Onsen, a peaceful outdoor bath located less than an hour from downtown Kyoto. Located in a lovely modern ryokan (traditional inn), with stunning mountain views, Kurama is surrounded by Japanese cedar trees. Traditional ryokan with hot spring baths include Gyozanen and Seryo, two beautifully designed resorts in Ohara, a rural district north of downtown, near the Sanzenin Temple.

Health benefits and bathing etiquette
Balneotherapy, the use of bathing as a form of medical treatment, is widely practiced in Japan. Although generally considered an “alternative medicine”, balneotherapy’s benefits have been demonstrated by global peer-reviewed medical studies. The chemistry, temperature, pressure and buoyancy of thermal baths have curative properties used to treat skin conditions such as dermatitis, inflammation-related conditions such as arthritis and musculoskeletal conditions such as lower back pain.

The sulfur and magnesium found in hot springs promotes skin health, while the heat of these baths can reduce inflammation and pain, and boost the immune system. Japanese onsen must be at least 25C, though some get as hot as 100C.

Onsen bathing is an important part of Japanese culture, and proper etiquette is well-established. The following tips should help you through your first experience.

Rinse off before going in
Depending on the facility you visit, you must either rinse off with tap water or scrub down with soap and tap water before entering the thermal bath. Bring your own soap, shampoo and towel just in case.

Take it all off
Most onsen do not allow swim suits. At these spas, there are separate baths for men and women. You can use a towel to cover up when outside of the spring water – just be sure not to let that towel fall into the bath, since the goal is the keep the water as clean as possible.

Check beforehand about an onsen’s “tattoo policy”
According to the site OnsenJapan, tattoos have traditionally signified gang or organized crime ties. While it may be discriminatory, some onsen are still not open to people with tattoos.

Do not take pictures
Many onsen do not allow photography. If you wish to photograph the surrounding scenery, ask the resort staff before taking any chances.

Drink water not booze
Drink bottled water to stay hydrated. Alcoholic beverages are not recommended as prolonged exposure to hot water can be dangerous if you are intoxicated. 

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