The Ultimate Guide to Japan Onsen

Thinking of visiting a Japanese onsen? Whether you're dreaming of a serene mountain bath or a luxury ryokan getaway, this guide will walk you through everything you need to know about onsen culture in Japan—from where to go, what kinds of baths to try, and how to make the most of the experience.

Not sure about the rules or what to expect when you bathe? Be sure to also check out our complete guide to onsen etiquette for a step-by-step breakdown on how to use an onsen like a local.

What Is an Onsen? (And How Is It Different from a Sento?)

A Japanese onsen（温泉） is a hot spring bath naturally heated by geothermal energy. It’s often rich in minerals and used for health, relaxation, and cultural ritual.

Not to be confused with sento（銭湯）, which are regular public bathhouses using heated tap water, onsen are typically:

Located in nature-rich areas or traditional inns (ryokan)

Fed by natural spring sources

Said to help with skin, circulation, and muscle recovery

Japan is home to many unique onsen, from wild outdoor rotenburo baths to high-end onsen resorts.

A Short History of Onsen

The earliest written mentions of onsen date back over 1,000 years. In the Nara period (8th century), they were considered medicinal. Over time, they evolved into leisure destinations—first for aristocrats and samurai, and later for common folk during the Edo period. Famous onsen towns like Kusatsu, Beppu, and Hakone developed into full-on hot spring resorts.

You can visit museums like Beppu Kannawa Jigoku Onsen Museum to learn more about how they form. (I highly recommend - it was a very cool interactive experience!)

What types of baths are in Japan?

Public Onsen (銭湯 / Sento)

These are communal bathhouses, typically separated by gender. Some sento use regular heated water, but many incorporate natural spring water. They’re inexpensive and a great way to mingle with locals.

Try: Takaragawa Onsen Osenkaku in Gunma for a dramatic riverside outdoor bath.

Ryokan Onsen (旅館)

Staying at a traditional inn? Most ryokan offer access to their own onsen, often with beautiful views and cozy rooms with tatami mats. Meals usually include seasonal kaiseki (懐石) cuisine.

Try: Gora Kadan in Hakone, a luxury ryokan with refined service and serene private baths.

Private Onsen (貸切温泉)

Prefer more privacy? Many onsen inns offer kashikiri (private) baths for couples, families, or anyone shy about communal nudity.

Try: Yama no Chaya in Hakone, offering elegant private baths with mountain views.

Themed or Unusual Onsen

In places like Oita or Hakone, you’ll find sand baths, mud baths, cave baths, and even wine or green tea baths—fun twists on tradition.

Try Yunessun for wine and coffee-themed baths.

Where can I find hot springs in Japan?

Japan is full of great hot springs areas. In Beppu, you’ll find mud baths and steaming "hells"; in Kusatsu, sulfur-rich springs and traditional yumomi performances; and in Hakone, elegant ryokan with Mt. Fuji views.

And Japanese onsen aren’t just places to unwind—they’re often settings straight out of a movie. Ikaho Onsen in Gunma is one such spot. Its nostalgic wooden inns and the red Kajika-bashi（河鹿橋） bridge are said to have inspired the bathhouse and iconic bridge scenes in Spirited Away. Walking through its misty alleys, you almost expect to see a spirit or soot sprite passing by.

These towns are immersive destinations where centuries of bathing tradition live on, and certainly worth a visit!

🛁 What’s Inside an Onsen? Common Types of Baths You’ll Find

Some onsen are minimal and traditional, others are sprawling complexes with over a dozen pools, each offering a different way to soak and relax.

Here are some of the most common types of baths you might encounter:

大浴場（だいよくじょう）– Main Bath

This is the central indoor bath, often filled with mineral-rich hot spring water. It’s usually the largest bath in the facility, with wide tiled walls, mirrors, and calm lighting. Think of it as the “default” soak.

露天風呂（ろてんぶろ）– Outdoor Bath

An open-air bath, rotenburo lets you enjoy fresh air, natural scenery, or starry skies while you soak. Many people say this is their favorite part of the onsen experience—especially in winter, when snow piles up just beyond the water’s edge.

ジェットバス – Jet Bath

Popular in modern super sento and wellness-style onsen, these use water pressure to massage your back, legs, or shoulders. It’s a nice choice after a long travel day or hike, and tends to be warmer and more stimulating than a standard bath.

寝湯（ねゆ）– Reclining Bath

In a neyu, you recline in shallow water with your back supported and just enough heat to lull you into a near-nap. It’s not too hot, and perfect for people who want to rest without getting overheated.

壺湯（つぼゆ）– Pot Bath

These charming single-person ceramic pots are filled with hot spring water and placed slightly apart from the main bath. Sitting in your own tsuboyu is a quiet, almost private way to soak—often with a view.

水風呂（みずぶろ）– Cold Bath

This cold plunge bath is used after a hot soak or a sauna session. It helps refresh the body and tighten pores—and gives you a refreshing “reset” between rounds of bathing.

炭酸泉（たんさんせん）– Carbonated Bath

A warm bath with naturally or artificially infused carbonation. The fine bubbles feel like champagne on your skin, and the gentle pressure is said to improve circulation. It’s especially popular among regular onsen-goers.

歩行湯（ほこうゆ）– Walking Bath

A shallow bath designed for low-impact walking, often with textured floors to massage the feet. It’s not always present, but common in wellness or rehabilitation-style bathhouses. Great for older visitors or anyone looking to relax tired legs.

You don’t have to try them all—but part of the fun of visiting a Japanese onsen is exploring the variety.

🌿 Why Japanese People Love Onsen: Health Benefits and More

For many Japanese people, onsen is a part of a wellness routine deeply tied to nature and tradition. Each onsen has a unique mineral composition, and these minerals can have different effects on the body.

According to the Japan Spa Association, the benefits of onsen are both physical and mental:

Sulfur springs（硫黄泉）: Known for their distinctive smell, sulfur-rich waters are believed to help with skin conditions like eczema and promote joint relief.

Iron-rich springs（含鉄泉）: Reddish-brown in color, these waters may help with iron deficiency and anemia.

Carbonated springs（炭酸水素塩泉 / 炭酸泉）: Gentle bubbles stimulate blood flow and improve circulation—great after a long day of walking or hiking.

Sodium chloride springs（塩化物泉）: Often called “heat-retaining baths,” these help warm the body deeply and relieve fatigue or cold sensitivity.

Beyond the science, the act of soaking itself lowers stress, soothes muscle tension, and even improves sleep. It's no surprise that many Japanese people say they sleep more soundly after an evening onsen soak.

Modern Takes on Onsen

While traditional hot spring bathing remains timeless, many onsen facilities today are embracing playful, creative twists that blend culture, comfort, and a bit of fun.

🏞️ Onsen Theme Parks

Looking for something a little more unexpected? Places like Yunessun in Hakone offer hot spring amusement parks, complete with wine baths, waterslides, and outdoor lounging zones.

☕ Onsen + Café Combos

Some onsen now have hip cafes or lounges attached, perfect for relaxing after a soak. Try a matcha latte with a view of Mt. Fuji.

🎉 Local Festivals

Onsen towns often host festivals celebrating their waters. You’ll find yukata parades, open-air markets, and free entry days.

🧳 Tips for First-Time Onsen Visitors

If it’s your first time at a Japanese onsen, a little preparation goes a long way. Here are a few practical tips to help you feel comfortable and make the most of your visit:

Bring a towel (or rent one): Most onsen don’t provide free towels, so bring a small towel for washing and a larger one for drying off. If you forget, you can usually rent or buy them at the front desk. They're typically around 100-300 yen depending on the location. Ryokans will usually tell you to use the towel in your room.

Stay hydrated: Hot spring bathing can be surprisingly dehydrating. Drink water before and after your soak to avoid dizziness or fatigue.

Avoid entering right after eating or drinking alcohol: Let your body digest before entering hot water. Bathing on a full stomach or after drinking can lead to nausea or overheating.

Visit during off-peak hours if you’re shy: If you're nervous about communal bathing, try going early in the morning or late at night when the baths are quieter. Many onsen are open from dawn to late evening, offering peaceful moments with fewer people around.

Vocabulary for Japan Onsen Essentials

温泉 (onsen) – hot spring

旅館 (ryokan) – traditional Japanese inn

銭湯 (sento) – public bathhouse

懐石料理 (kaiseki ryōri) – traditional multi-course meal

湯 (yu) – hot water

貸切温泉 (kashikiri onsen) – private onsen

入浴 (nyūyoku) – bathing

洗い場 (araiba) – wash area

湯上がり (yuagari) – post-bath glow

Ready to experience Japan’s ultimate form of relaxation? Whether you’re headed for a remote mountain inn or a modern city bathhouse, onsen culture is a gateway to deeper connection—with Japan, nature, and yourself. 🛁🌿