Hot springs Overview

What Are Hot Springs

A hot spring, or onsen (温泉) as its called in Japanese, is a place where hot water or a hydrothermal spring spouts out of the ground.
There are two main types of hot springs: volcanic hot springs caused by volcanic gases spewed from underground magma, and non-volcanic hot springs that are heated by geothermal heat from the groundwater.
There are also some hot springs whose heat source is unknown.
A hot spring resort is a place where the hot water spouting out of a hot spring is maintained and made into a bathing facility.

Japan is known as one of the world's leading hot spring countries, due in part to its many volcanoes.
According to statistics from the Ministry of the Environment, there are currently more than 3,000 hot spring resorts throughout Japan.
The largest number of hot spring resorts is in Hokkaido, with a whopping 251 resorts.
On the other hand, Okinawa Prefecture has the least number of hot springs, with just 4.

The History of Japan's Hot Springs

The history of hot springs in Japan is ancient, with passages about them even being found in texts such as the Nihon Shoki (Chronicles of Japan).
Tamatsukuri Onsen, Arima Onsen, Dogo Onsen, Shirahama Onsen, and Akiu Onsen are the oldest existing hot springs in Japan, and are said to have been used as hot springs since before the Heian period (794 to 1185).
The "Engishiki Shinmeicho," a book about shrines in Japan written in the Heian Period, describes onsen shrines that deify the kami (gods) of hot springs.

Following the Kamakura period (1192-1333), a movement to utilize hot springs for medicinal purposes began to spread.
The custom of bathing became common after monks such as Ippen used them, and it became more practical when those injured during the Mongol invasions of Japan used the hot springs to recuperate.
During the Warring States period, it is said that warlords such as Takeda Shingen and Uesugi Kenshin used hot springs regularly.
During the Edo period, visitors to hot springs during the slack season of farming increased, and the number of overnight guests increased in various places, creating a style similar to that of today's hot springs.
After the Meiji period, the technology of drilling for hot springs became widespread, and hot spring towns began popping up all over the country.

In the Showa Period (1926-1989), Kyushu University established a research center for hot spring therapy at Beppu Onsen, and today, the components of hot springs are scientifically researched.
As the research demonstrated the medical effects of hot springs, the number of hot spring users skyrocketed.
In addition, during the Showa period, many hot spring resorts were built all over Japan as a form of leisure for families to enjoy, giving them a lively, resort-like atmosphere.
In recent years, with the intention of utilizing the health benefits of hot springs, some hot spring inns have linked with hospitals to provide accommodation plans for people who have undergone comprehensive medical check-ups.
In addition, Fukushima Prefecture has a racehorse rehabilitation center that offers hot springs for injured horses.

The Components and Benefits of Japan's Hot Springs

Japan's hot springs are defined in accordance with the rules of the Hot Springs Law (温泉法) and the Guidelines for the Analysis of Mineral Springs for Tourism (観光症の鉱泉分析法指針).
Depending on the temperature of the hot spring water coming out of the ground, hot springs are divided into four types: cold springs, low temperature springs, hot springs, and high temperature springs.
Another important factor of onsen is the amount of water that comes out of the spring and the quality of the dissolution.
There are a variety of components found in Japan's hot springs, including lithium ions, strontium ions, barium ions, fluorine ions, hydrogen arsenate ions, meta-arsenic acid, metaboric acid, sulfur, metasilicic acid, radon, radium, and more.

These ingredients have many other benefits, such as relieving fatigue, relieving nerve and muscle pain, relief from sore shoulders and back pain, alleviating illnesses, promoting healthy skin, and improving health.
There are two types of hot spring services: a recirculating type, in which hot water is re-injected, and a flowing type, in which water is not reused.
For circulating hot springs, hot water is filtered, heated and injected again, so there are no hygiene problems.
In recent years, however, more and more hot spring users prefer to use flowing style onsen.

Type of Hot Springs in Japan

Many people go on hot spring trips for leisure and to relax.
There are many hotels and inns in hot spring villages and hot spring towns, where you can enjoy a relaxing bath.
Some onsen facilities offer day trips in addition to overnight plans, which are popular because it makes it easy to stop by and enjoy the springs without having to commit to an overnight stay.

In Japan, in addition to natural onsen, there are also artificial onsen facilities.
In recent years, there has been an increase in the number of so-called "super sento" onsen, which are equipped with artificial hot springs.
Super sento are reasonably priced suburban hot springs that are equipped with jacuzzis, saunas and open-air baths, as well as restaurants and other convenient facilities.
In addition to artificial hot springs, there are also resort-style super sento with natural hot springs, which are always crowded with customers.
There are many public baths used by locals in old-fashioned towns as well.
Although the number of public baths in towns is decreasing as the bathrooms in ordinary houses are becoming more and more comfortable, there are still many people in some areas who still prefer to use public baths with a retro atmosphere.

Bathing at Japan's Hot Springs

When most people hear the word "hot spring," they associate it with relaxing in a large public bath, but there are many other ways to enjoy hot springs.

Utase-yu (打たせ湯): A type of bath where the water falls from above like a waterfall and in doing so massages the shoulders and back to relieve pain.
Tachi-yu (立ち湯): Tachi-yu are deep standing baths that can be enjoyed while standing as opposed to sitting.
Ne-yu (寝湯): Ne-yu are shallow, lie down baths.
Ashi-yu (足湯): Ashi-yu are footbaths that you can soak you're feet in. They're easy to use and great for when you don't feel like getting your whole body wet.
Mushi-yu (蒸し湯): These are steam baths. In general, there are two types- stone room steam baths and box saunas.
Suna-ya (砂湯): An unusual type of hot spring that is buried in hot sand.
Ganban'yoku (岩盤浴): Essentially hot stone spas, this is a type of hot spring facility where you can enjoy lying down on a warm bedrock and sweat.
Doro-yu (泥湯): Doro-yu are mud baths.

Mud baths are not just used for bathing, but also for selling hot spring mud and hot-springs' mineral deposits as bath salts and skin care products.
Hot springs can also be used for food processing, such as the Jigokugama (hell kettle), which uses the heat of hot springs to steam fish and vegetables, and hot spring eggs, which are boiled in hot spring water.

Check Out This List of Popular Hot Springs!

The following is a ranking of the most popular hot springs destinations for the first half of 2020, as announced by the major travel website Rakuten Travel.
They are all recommended for couples, families, women's trips, and group trips, so if there's an onsen that interests you, be sure to throw it on your itinerary!

No. 1 Atami Onsen (Shizuoka Prefecture)
No. 2 Beppu Hot Spring (Oita)
No. 3 Kusatsu Onsen (Gunma Prefecture)
No. 4 Hakodate Onsen/Yunokawa Onsen (Hokkaido)
No. 5 Kinugawa Onsen (Tochigi Prefecture)
No. 6 Gero Onsen (Gifu)
No. 7 Akiu Hot Spring (Miyagi)
No. 8 Shirahama Onsen (Wakayama, Japan)
No. 9 Nasu Onsen (Tochigi Prefecture)
No. 10 Ito Hot Spring (Shizuoka)
No. 11 Ikaho Hot Spring (Gunma)
No. 12 Hakone-Yumoto Onsen (Kanagawa Prefecture)
No. 13 Gora Hot Spring (Kanagawa)
No. 14 Arima Hot Spring (Hyogo)
No. 15 Kinosaki hot spring (Hyogo)
No. 16 Dogo Hot Spring (Ehime)
No. 17 Echigo Yuzawa Onsen (Niigata Prefecture)
No. 18 Toba hot spring village (Mie)
No. 19 Yufuin Hot Spring (Oita)
No. 20 Jozankei Onsen (Hokkaido)

Hot springs areas such as Atami, Hakone, Kusatsu, and Kinugawa are close to Tokyo, Saitama, and Kanagawa, all of which are in Japan's Kanto region and are easily accessible.
For those in the Kansai region, trips to Arima Onsen, Kinosaki Onsen, and Shirahama Onsen are popular.
Those in the Tokai region often go to Gero Onsen or "Toba Onsen Go."

Hidden Hot Springs in Japan

In Japan, in addition to the famous hot springs, there are also many hidden hot springs that are rarely visited but amazing nonetheless.
Most of them are located deep in the mountains or in other inaccessible locations, and the area around the hot springs is usually poorly maintained.
One of the most popular of these hidden hot springs is Takamagahara Onsen, which is located approximately 2,100 meters above sea level in Toyama Prefecture.
Other secluded hot springs include Sennin Onsen in Toyama Prefecture, Kurogane Onsen in Fukushima Prefecture, and Hakubayari Onsen and Honzawa Onsen in Nagano Prefecture.
When you visit these hidden hot springs, you'll have to prepare mountain climbing equipment and walk for several hours along the mountain path, which can be a lot of work.
However, the hot springs you'll find waiting for you are surrounded by spectacular scenery and the healing power of the springs is exceptional.

Spend Time Healing in Japan's Hot Springs

There are many hot springs in Japan, ranging from famous hot springs that are well known to everyone, to hidden hot springs that only a handful of people know about.
Hot springs come in a variety of forms, including general public baths, mixed bathing where men and women wear swimsuits, and family baths that can be enjoyed by families.
The appeal of hot springs is that you can relax and enjoy the health benefits as well.
Take a trip to a relaxing hot spring and enjoy a wonderful time with your family, friends, loved ones, or on your own!