Onsen in Japan
What an onsen is, how it works, its rules, and my honest experience at Gero Onsen and the Suimeikan ryokan.
A Japanese tradition that goes far beyond bathing
One of the most traditional experiences you can have in Japan is bathing in an onsen, a natural hot-spring bath. For Japanese people, it is not simply about getting into hot water: it is a way to relax, switch off, care for the body, and enjoy a deeply rooted tradition.
If you have never visited one, it is normal to have questions: do you have to enter naked, can you wear a swimsuit, and what happens if you have tattoos? In this guide, I explain how it works and share my honest opinion after trying one in Gero.
What is an onsen?
An onsen is a natural hot-spring bath supplied by geothermal sources. The water usually contains minerals and is considered beneficial for the body and relaxation in Japan.
It is neither a swimming pool nor a Western-style spa: people do not go there to swim, play, or make noise, but to bathe calmly and respect the peaceful atmosphere. Baths are usually separated by gender, although private baths known as kashikiri onsen are also available for individuals, couples, or families.
You will find them in hotels, ryokan, hot-spring towns, and natural settings. They may be indoors or outdoors, and some of the most beautiful are surrounded by mountains and gardens.
Gero Onsen and the Suimeikan ryokan
Gero Onsen is considered one of Japan’s three most famous onsen, alongside Kusatsu and Arima. It holds an important place in Japanese hot-spring culture.
I stayed at the Suimeikan ryokan in a traditional room with tatami mats, a low tea table, and beautiful, peaceful, meticulously maintained surroundings. There were several onsen areas, and one remained open 24 hours, making it ideal for visiting at a quieter time.
Although the shared bath was not the part I enjoyed most, I found the place genuinely special. If I tried an onsen again, I would consider returning there or booking a private one.
How does an onsen work?
The process is simple. Enter the appropriate changing room and leave your clothes, shoes, and belongings in a locker or basket. Then move to the shower area and wash thoroughly before entering the hot-spring water.
Enter slowly, as the water is usually very hot. You do not need to stay in for long at a time; you can get out, rest, and enter again. When you finish, dry yourself a little before returning to the changing room so you do not wet the floor.
Basic rules for visiting an onsen
- Shower first. Everyone must be completely clean before entering.
- No swimsuits. Most onsen are entered without clothing.
- Keep the towel out of the water. It must not touch the hot-spring water.
- No photos or videos. This is a matter of privacy and respect.
- Do not swim or splash. This is a place for relaxation.
- Tie up long hair. It must not touch the water.
- Avoid alcohol. The heat may cause dizziness.
- Listen to your body. Get out if you feel too hot.
A note about tattoos
Some onsen still restrict entry for people with tattoos. In my case, Suimeikan did not require small tattoos to be covered, but this may depend on the property, tattoo size and location, or the rules in force at the time.
Always check the rules before visiting. If you have large tattoos, look for a tattoo-friendly onsen, ask the ryokan directly, bring covering patches if requested, or book a private bath.
What to bring to an onsen
A ryokan will normally provide towels, a yukata, and everything else you need. Even so, bring a hair tie, leave your phone outside the bathing area, drink water before and after, and avoid staying in the hot water for too long at once.
Above all, keep an open mind: it is a very different experience from what we are used to in Spain.
My personal experience at Gero Onsen
I want to be honest: personally, it was not an experience I particularly enjoyed. I am very glad I tried it because it is part of Japanese culture, but I did not feel entirely comfortable being naked in a shared hot-spring bath.
What surprised me most was the immense respect with which the experience is approached. Nobody stares at you or invades your space; the Japanese women were very respectful, and everyone enjoyed the bath completely naturally. My discomfort did not come from anyone else, but from not being used to it.
I am glad I experienced it, but I would not pay to repeat it just anywhere. I would return to Suimeikan for its beautiful traditional surroundings and would preferably choose a private onsen or a room with its own hot-spring bath.
Is an onsen in Japan worth trying?
Yes, if you are curious about experiencing something deeply Japanese, although it is perfectly fine if it is not for you. Many people consider onsen one of the highlights of their trip; for me, it was mainly a way to understand the culture better.
If you feel shy or uncomfortable in a public bath, book a private onsen, look for a ryokan with a hot-spring bath in the room, or simply enjoy the traditional accommodation without using the shared baths.
Tips for your first visit
- Take your time and observe what local people do.
- Shower thoroughly before entering.
- Do not let your towel or hair touch the water.
- Respect the quiet atmosphere and other people’s space.
- Do not stay in too long if the water is very hot.
- Do not force yourself: it is fine if it is not for you.
7. Frequently asked questions
Do you have to enter naked?
Yes, in most public onsen. If this makes you uncomfortable, choose a private bath.
What if I have tattoos?
It depends on the property. Suimeikan did not ask me to cover small tattoos, but always check in advance.
Private or public onsen?
A public onsen offers the traditional experience; a private one provides more privacy and may be better for a first visit.
Is it worth it?
Yes, as a cultural experience, provided you want to try it and feel comfortable.
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