What are sulfur hot springs? Learn their place among medicinal springs, top spots like Takayu, Manza, and Tsukioka, regional differences, how to bathe, what to bring, and common indications.
Published: Dec 24, 2025
What are sulfur hot springs? Learn their place among medicinal springs, top spots like Takayu, Manza, and Tsukioka, regional differences, how to bathe, what to bring, and common indications.
Published: Dec 24, 2025
Sulfur springs have a distinctive scent and milky-white water that feels like the very image of an onsen. One of Japan’s signature hot spring types in its volcanic landscape, they can be found in famous bath spots across the country. If you want to try a sulfur spring, the first things you may want to know are what kind of hot spring it is, where you can find one, and how best to enjoy it.
In short, sulfur springs are one type of medicinal spring, and their smell, color, and level of irritation can differ greatly from one hot spring area to another. That is why the key is not chasing the most famous one, but finding a bath that feels comfortable for you. This article explains the role of sulfur springs, famous examples and regional characteristics, how to bathe, what to bring, and the indications commonly associated with medicinal springs for first-time visitors.
For the scientific reasons behind the egg-like smell and cloudy water, silver discoloration, and gas precautions in poorly ventilated places, see The Smell and Color of Sulfur Springs. For the full picture of the 10 spring types, see Guide to Onsen Spring Types. Here, we focus on sulfur springs themselves.
This article provides general information. If you have concerns about your health or a chronic condition, please do not overdo it and follow the advice of a doctor or the facility.
If you see signs such as "sulfur spring" or "sulfur-containing sodium chloride spring" at a hot spring area, you can think of it as a medicinal spring that meets the standards set by the Ministry of the Environment. A medicinal spring refers to a hot spring that meets stricter standards with treatment use in mind, and the familiar spring-name labels such as "__ spring" are used only for this category.
For sulfur springs, the Ministry of the Environment’s "Guidelines for Mineral Spring Analysis Methods" defines them as springs containing at least 2 mg of total sulfur per 1 kg of hot spring water. The details of this definition, and the difference between the strongly smelly "hydrogen sulfide type" and the gentler "simple sulfur type," are covered in The Smell and Color of Sulfur Springs. For now, it is enough to know that if the sign says sulfur spring, it meets the standard.
What matters most is that not all sulfur springs are the same. Some are nearly clear, while others are milky-white. Some are strongly acidic and sharp, while others are rarely alkaline and smooth. A sulfur spring is not always white, cloudy, and intensely smelly.
Sulfur springs are found widely from Hokkaido to Kyushu, often linked to volcanic areas. Among them, Takayu Onsen in Fukushima, Manza Onsen in Gunma, and Tsukioka Onsen in Niigata are often called the Three Great Sulfur Springs of Japan. The following table summarizes famous sulfur springs and their local character.
| Hot Spring Area | Location | Character / Tendencies |
|---|---|---|
| Takayu Onsen | Fukushima Prefecture | A mountain hot spring on the slopes of the Azuma mountain range, long known as a famous bath with rich sulfur content |
| Manza Onsen | Gunma Prefecture | A highly acidic sulfur spring at an altitude of about 1,800 m, known for its abundant flow |
| Tsukioka Onsen | Niigata Prefecture | Rarely alkaline for a sulfur spring, with a greenish bath color |
| Noboribetsu Onsen | Hokkaido | A hot spring area with Jigokudani and a variety of spring types, including sulfur springs |
| Kusatsu Onsen | Gunma Prefecture | A famous therapeutic hot spring resort known for its strong acidity and sulfur content |
| Unzen Onsen | Nagasaki Prefecture | A signature sulfur spring of Kyushu, alongside the steam vents of Unzen Jigoku |
As the table shows, sulfur springs range widely from high-altitude acidic waters to lowland alkaline waters. Even within the same hot spring area, the source used by each inn or public bath can differ, changing the smell and the degree of cloudiness. Rather than thinking that all sulfur springs are the same, it is more enjoyable to appreciate the character of each area and each facility.
If you like strong, stimulating waters, acidic springs such as Manza or Kusatsu may suit you. If you want a smoother feel on the skin, alkaline Tsukioka may be a better choice. When searching by area or condition, it helps to narrow down the options and compare them from Facility List.
The basic way to bathe in a sulfur spring is the same as in other spring types. Rinse your body with a shower or splash of hot water first, do not stay in too long at the start, get out before you feel overheated, and drink plenty of water before and after. These simple steps greatly reduce the strain on your body.
A sulfur spring-specific tip is to start with short exposure if the water is rich in minerals and highly stimulating. Strongly acidic waters can sometimes tingle the skin, so people with sensitive skin should adjust their bathing time while watching how they feel. If you start to feel unwell from the bath, it is safest to get out once rather than forcing yourself to stay in.
As for enjoyment, it is fun to notice how the bath color and the visible mineral deposits change depending on the time of day and the tub. Milky-white cloudy water is also great for photos, and in an open-air bath you can enjoy the mountain scenery together with the atmosphere unique to sulfur springs. Many people also enjoy the smell itself as proof that they have come to a real hot spring. If you do not like strong odors, there is no need to choose a powerful sulfur spring; you can also try a gentler simple sulfur spring or another spring type. You can compare the tendencies of each spring type in Guide to Onsen Spring Types.
If you are going to a sulfur spring, the basic rule is to remove silver accessories beforehand. They can react with sulfur and turn black in a short time, and in some hot spring areas they may discolor even just by walking around without entering the water. Rings, necklaces, earrings, and the like are best left in your room or locker.
For the mechanism behind this discoloration, and for gas precautions in poorly ventilated areas, see The Smell and Color of Sulfur Springs. In general, there is no need to worry excessively in normal public bathing facilities, but you should always follow any no-entry signs around source areas or steam zones.
Among medicinal springs, sulfur springs are often discussed in relation to skin-related indications. According to the Ministry of the Environment’s guidelines, bathing indications for sulfur springs include skin conditions such as atopic dermatitis and chronic eczema, while drinking indications include impaired glucose tolerance, including diabetes. For this reason, they are sometimes called "skin hot springs."
However, these indications are only based on the idea of repeated use over a certain period, as in spa treatment, and they do not guarantee results from a single bath. Individual responses vary greatly, and some people find the water pleasantly stimulating while others feel it is too strong. This article does not claim any specific effects; it only notes what is generally said about medicinal springs. Rather than expecting too much in terms of beauty or treatment, it is more reasonable to enjoy it as one of the many unique waters of a volcanic country.
If you have concerns about your health or chronic conditions, or if you are older, it is a good idea to check Precautions Before Entering a Hot Spring before bathing, not only for sulfur springs but for all hot springs. Also, there are spring types that are completely different from sulfur springs, such as radon-bearing radioactive springs, so trying different waters and finding the one that suits you is part of the fun of hot springs.
They are scattered across volcanic regions throughout Japan. Representative examples include Takayu Onsen in Fukushima, Manza Onsen in Gunma, and Tsukioka Onsen in Niigata, often called the Three Great Sulfur Springs of Japan. Noboribetsu, Kusatsu, and Unzen are also known for sulfur-rich waters. Even within the same hot spring area, each facility may use a different source.
No. Some waters are nearly clear, while others are milky-white and cloudy, and the strength of the smell varies widely. There are also sulfur springs with a gentle scent and, rarely, alkaline sulfur springs with a smooth feel. The mechanism behind the color and smell is explained in The Smell and Color of Sulfur Springs.
Remove silver accessories because they may discolor. If the water is highly mineralized or strongly acidic, start with a short soak, and if you feel unwell, get out without forcing yourself. For ventilation and gas precautions, see The Smell and Color of Sulfur Springs.
They are generally discussed as medicinal springs with indications for skin conditions, but this article does not claim any specific effects. The indications are based on repeated use over a period of time, and individual differences are large, so do not expect too much.
There is no need to force yourself to choose a strong sulfur spring. You can choose a gentler one, or try a simple hot spring or a bicarbonate spring, which tend to have fewer quirks. You can compare the characteristics of each spring type in Guide to Onsen Spring Types.
Sulfur springs are one type of medicinal spring and a distinctive hot spring style that represents volcanic Japan. Famous baths are scattered across the country, led by Takayu, Manza, and Tsukioka, and their regional character ranges widely from strong acidic waters to smooth alkaline ones. That is why it is more enjoyable not to think of all sulfur springs as the same, but to appreciate the differences between each area and each facility.
The basics of bathing are the same as with other spring types: start with short exposure if the water is strong, and remove silver jewelry. Although sulfur springs are often discussed in terms of medicinal indications, it is best not to expect too much and instead focus on finding one bath that feels comfortable to you. Detailed notes on the science of smell, cloudiness, and safety are gathered in The Smell and Color of Sulfur Springs.
Sulfur springs have a distinctive scent and milky-white water that feels like the very image of an onsen. One of Japan’s signature hot spring types in its volcanic landscape, they can be found in famous bath spots across the country. If you want to try a sulfur spring, the first things you may want to know are what kind of hot spring it is, where you can find one, and how best to enjoy it.
In short, sulfur springs are one type of medicinal spring, and their smell, color, and level of irritation can differ greatly from one hot spring area to another. That is why the key is not chasing the most famous one, but finding a bath that feels comfortable for you. This article explains the role of sulfur springs, famous examples and regional characteristics, how to bathe, what to bring, and the indications commonly associated with medicinal springs for first-time visitors.
For the scientific reasons behind the egg-like smell and cloudy water, silver discoloration, and gas precautions in poorly ventilated places, see The Smell and Color of Sulfur Springs. For the full picture of the 10 spring types, see Guide to Onsen Spring Types. Here, we focus on sulfur springs themselves.
This article provides general information. If you have concerns about your health or a chronic condition, please do not overdo it and follow the advice of a doctor or the facility.
If you see signs such as "sulfur spring" or "sulfur-containing sodium chloride spring" at a hot spring area, you can think of it as a medicinal spring that meets the standards set by the Ministry of the Environment. A medicinal spring refers to a hot spring that meets stricter standards with treatment use in mind, and the familiar spring-name labels such as "__ spring" are used only for this category.
For sulfur springs, the Ministry of the Environment’s "Guidelines for Mineral Spring Analysis Methods" defines them as springs containing at least 2 mg of total sulfur per 1 kg of hot spring water. The details of this definition, and the difference between the strongly smelly "hydrogen sulfide type" and the gentler "simple sulfur type," are covered in The Smell and Color of Sulfur Springs. For now, it is enough to know that if the sign says sulfur spring, it meets the standard.
What matters most is that not all sulfur springs are the same. Some are nearly clear, while others are milky-white. Some are strongly acidic and sharp, while others are rarely alkaline and smooth. A sulfur spring is not always white, cloudy, and intensely smelly.
Sulfur springs are found widely from Hokkaido to Kyushu, often linked to volcanic areas. Among them, Takayu Onsen in Fukushima, Manza Onsen in Gunma, and Tsukioka Onsen in Niigata are often called the Three Great Sulfur Springs of Japan. The following table summarizes famous sulfur springs and their local character.
| Hot Spring Area | Location | Character / Tendencies |
|---|---|---|
| Takayu Onsen | Fukushima Prefecture | A mountain hot spring on the slopes of the Azuma mountain range, long known as a famous bath with rich sulfur content |
| Manza Onsen | Gunma Prefecture | A highly acidic sulfur spring at an altitude of about 1,800 m, known for its abundant flow |
| Tsukioka Onsen | Niigata Prefecture | Rarely alkaline for a sulfur spring, with a greenish bath color |
| Noboribetsu Onsen | Hokkaido | A hot spring area with Jigokudani and a variety of spring types, including sulfur springs |
| Kusatsu Onsen | Gunma Prefecture | A famous therapeutic hot spring resort known for its strong acidity and sulfur content |
| Unzen Onsen | Nagasaki Prefecture | A signature sulfur spring of Kyushu, alongside the steam vents of Unzen Jigoku |
As the table shows, sulfur springs range widely from high-altitude acidic waters to lowland alkaline waters. Even within the same hot spring area, the source used by each inn or public bath can differ, changing the smell and the degree of cloudiness. Rather than thinking that all sulfur springs are the same, it is more enjoyable to appreciate the character of each area and each facility.
If you like strong, stimulating waters, acidic springs such as Manza or Kusatsu may suit you. If you want a smoother feel on the skin, alkaline Tsukioka may be a better choice. When searching by area or condition, it helps to narrow down the options and compare them from Facility List.
The basic way to bathe in a sulfur spring is the same as in other spring types. Rinse your body with a shower or splash of hot water first, do not stay in too long at the start, get out before you feel overheated, and drink plenty of water before and after. These simple steps greatly reduce the strain on your body.
A sulfur spring-specific tip is to start with short exposure if the water is rich in minerals and highly stimulating. Strongly acidic waters can sometimes tingle the skin, so people with sensitive skin should adjust their bathing time while watching how they feel. If you start to feel unwell from the bath, it is safest to get out once rather than forcing yourself to stay in.
As for enjoyment, it is fun to notice how the bath color and the visible mineral deposits change depending on the time of day and the tub. Milky-white cloudy water is also great for photos, and in an open-air bath you can enjoy the mountain scenery together with the atmosphere unique to sulfur springs. Many people also enjoy the smell itself as proof that they have come to a real hot spring. If you do not like strong odors, there is no need to choose a powerful sulfur spring; you can also try a gentler simple sulfur spring or another spring type. You can compare the tendencies of each spring type in Guide to Onsen Spring Types.
If you are going to a sulfur spring, the basic rule is to remove silver accessories beforehand. They can react with sulfur and turn black in a short time, and in some hot spring areas they may discolor even just by walking around without entering the water. Rings, necklaces, earrings, and the like are best left in your room or locker.
For the mechanism behind this discoloration, and for gas precautions in poorly ventilated areas, see The Smell and Color of Sulfur Springs. In general, there is no need to worry excessively in normal public bathing facilities, but you should always follow any no-entry signs around source areas or steam zones.
Among medicinal springs, sulfur springs are often discussed in relation to skin-related indications. According to the Ministry of the Environment’s guidelines, bathing indications for sulfur springs include skin conditions such as atopic dermatitis and chronic eczema, while drinking indications include impaired glucose tolerance, including diabetes. For this reason, they are sometimes called "skin hot springs."
However, these indications are only based on the idea of repeated use over a certain period, as in spa treatment, and they do not guarantee results from a single bath. Individual responses vary greatly, and some people find the water pleasantly stimulating while others feel it is too strong. This article does not claim any specific effects; it only notes what is generally said about medicinal springs. Rather than expecting too much in terms of beauty or treatment, it is more reasonable to enjoy it as one of the many unique waters of a volcanic country.
If you have concerns about your health or chronic conditions, or if you are older, it is a good idea to check Precautions Before Entering a Hot Spring before bathing, not only for sulfur springs but for all hot springs. Also, there are spring types that are completely different from sulfur springs, such as radon-bearing radioactive springs, so trying different waters and finding the one that suits you is part of the fun of hot springs.
They are scattered across volcanic regions throughout Japan. Representative examples include Takayu Onsen in Fukushima, Manza Onsen in Gunma, and Tsukioka Onsen in Niigata, often called the Three Great Sulfur Springs of Japan. Noboribetsu, Kusatsu, and Unzen are also known for sulfur-rich waters. Even within the same hot spring area, each facility may use a different source.
No. Some waters are nearly clear, while others are milky-white and cloudy, and the strength of the smell varies widely. There are also sulfur springs with a gentle scent and, rarely, alkaline sulfur springs with a smooth feel. The mechanism behind the color and smell is explained in The Smell and Color of Sulfur Springs.
Remove silver accessories because they may discolor. If the water is highly mineralized or strongly acidic, start with a short soak, and if you feel unwell, get out without forcing yourself. For ventilation and gas precautions, see The Smell and Color of Sulfur Springs.
They are generally discussed as medicinal springs with indications for skin conditions, but this article does not claim any specific effects. The indications are based on repeated use over a period of time, and individual differences are large, so do not expect too much.
There is no need to force yourself to choose a strong sulfur spring. You can choose a gentler one, or try a simple hot spring or a bicarbonate spring, which tend to have fewer quirks. You can compare the characteristics of each spring type in Guide to Onsen Spring Types.
Sulfur springs are one type of medicinal spring and a distinctive hot spring style that represents volcanic Japan. Famous baths are scattered across the country, led by Takayu, Manza, and Tsukioka, and their regional character ranges widely from strong acidic waters to smooth alkaline ones. That is why it is more enjoyable not to think of all sulfur springs as the same, but to appreciate the differences between each area and each facility.
The basics of bathing are the same as with other spring types: start with short exposure if the water is strong, and remove silver jewelry. Although sulfur springs are often discussed in terms of medicinal indications, it is best not to expect too much and instead focus on finding one bath that feels comfortable to you. Detailed notes on the science of smell, cloudiness, and safety are gathered in The Smell and Color of Sulfur Springs.