What is an onsen and why is it an almost sacred experience?

If you’ve ever seen pictures of Japan with mountains, steam rising from the water, and people relaxing in silence, you were probably looking at an onsen.. But what at first glance appears to be a hot bath is, in reality, one of the most authentic and profound experiences of Japanese culture.

Los onsen en Japón They’re not just places to relax: they represent tradition, a connection with nature, and, for many Japanese people, an almost spiritual experience. Understanding what an onsen is and how to experience it properly completely changes the way you experience Japan.

An onsen (温泉) It is a natural hot spring of volcanic origin whose hot waters emerge from the subsoil and contain minerals beneficial to the body. Japan, being a country with high volcanic activity, has thousands of these baths scattered throughout the territory.

But onsen is not just hot water: it is an ancient tradition deeply rooted in Japanese culture, linked to well-being, purification and rest.

This is where many people get confused.

• Onsen: natural, mineral-rich water of volcanic origin
• Sento: public bath with artificially heated running water

The sento is more urban and functional, while the onsen is an experience more linked to nature, ritual and well-being.

The water in onsen contains minerals such as sulfur, iron, or sodium, which are traditionally associated with health benefits, from improving skin to relieving muscle pain.

But beyond the physical, the value of the onsen is also cultural: since ancient times, bathing has been linked to spiritual purification in Japan.

Going to an onsen has its ritual, and that’s part of the magic:

1. You take off your clothes in the changing room (yes, completely)
2. You wash and rinse your body in the shower area
3. You enter the water already clean.
4. You relax in silence

It is important to understand that the onsen is not for “washing,” but for relaxing and disconnecting.

Respect is key in an onsen. Some essential rules:

• Shower before entering
• Do not put the towel in the water
• Maintain a low tone or silence
• No swimsuit required (entry is nude)

This set of rules helps to maintain the calm and respectful environment that characterizes onsen.

For many Japanese people, the onsen is a moment of total disconnection. There are no cell phones, no noise, no rush. Just you, the water, and your surroundings.

This combination of silence, nature, and tradition creates a profound sense of calm that transcends the physical. It’s a mental “reset” experience.

The rotenburo are probably the most iconic: outdoor toilets surrounded by nature.

Imagine immersing yourself in hot water while it’s snowing or surrounded by mountains. It’s one of the most memorable experiences you can have in Japan.

Many ryokan (traditional Japanese inns) include an onsen. Here the experience is more complete: tatami mats, yukata, Japanese dinner… and a hot spring bath.

It’s the most authentic way to integrate the onsen into your trip.

There are also onsen in cities, even in Tokyo. They are more accessible, modern, and adapted to the urban pace, but they maintain the essence of the ritual.

Japanese hot springs contain minerals that can:

• Improve circulation
• Relieve muscle tension
• Benefit the skin
• Reduce stress

It is no coincidence that they have been used as a natural treatment for centuries.

Beyond the physical aspect, the greatest benefit is mental.

Immersing yourself in an onsen means stopping, breathing, and disconnecting. In today’s fast-paced society, that has enormous value.

You don’t need much:

Small towel
Toiletries (although many onsen provide them)
Swimsuit (not usually used)

The simpler, the better.

Here’s the important part if you want to move around like someone who understands Japan:

• お湯 (oyu) → hot water / bath water
• 温泉 (onsen) → hot spring bath
• 露天風呂 (rotenburo) → outdoor onsen
• 男 / 女 (otoko / onna) → men / women (to identify areas)
• 入浴 (nyūyoku) → bathing (identify areas)
• 熱い (atsui) → hot
• ぬるい (nurui) → tempered
• 気持ちいい (kimochi ii) → “how pleasant” (very commonly used inside the onsen)
• すみません (sumimasen) → sorry / apology
• ありがとうございます (arigatou gozaimasu) → thank you

These words help you understand signs, communicate, and feel more comfortable.

Traditionally, tattoos have been associated with the yakuza, so some onsen prohibit them.

Opciones:

• Cover them with patches
• Search “tattoo friendly” onsen
• Book a private onsen

There is increasing flexibility, especially in tourist areas.

• Early morning
• Latest news of the day
• midweek

This way you can enjoy a more peaceful and authentic experience.

Visiting an onsen is not just “doing something typical”, it’s understanding how the Japanese experience rest, nature and balance.

When you immerse yourself in an onsen, you’re participating in a centuries-old tradition. And that completely changes your perspective on Japan.

At Doki Doki Japan we always say the same thing: Japan is not understood just by visiting temples or cities… it is understood by living experiences like this.

If you want to go beyond tourism and truly connect with the country, the onsen is one of those moments that changes everything.