Kose Onsen

8/10 Excellent - Based on 138 reviews

Traveler Mix:
Couples (33%)
Families (31%)
Solo travelers (24%)
Groups (12%)

Set against the forested slopes of Karuizawa in Nagano Prefecture, this single-building ryokan sits beside a mountain stream and offers a quietly secluded base for exploring nearby waterfalls and forest trails. Rooms are arranged in a traditional Japanese style with tatami space and futon bedding, and the property’s compact footprint lets many rooms look out over green slopes rather than busy streets. Access is more convenient by car—local buses serve the hotel but run infrequently—so guests planning day trips around Karuizawa often allow extra time for transfers.

The bathing facilities are a key draw: alongside a public indoor onsen there is a reservable open-air rotenburo for private use, fed by on-site sources with distinctly warm, mineral-rich water; some guests report that the private outdoor bath can be booked without extra charge. For travelers specifically seeking a ryokan with onsen Nagano, this property combines both communal bathing and a private open-air option that suits couples and families who prefer privacy. Water temperatures cited in local descriptions indicate separate source flows, and the compact layout makes multiple daily visits easy to fit around meals.

Meals lean toward seasonal Japanese set menus prepared on-site, with several guests noting a traditional multi-course experience and others mentioning occasional western-influenced items; staff service is consistently described as polite and attentive though English may be limited, so a few planning tips—confirm bus schedules and dinner availability in advance—are useful. The atmosphere is deliberately relaxed and somewhat retro, appealing to visitors after a calm onsen stay rather than contemporary luxury; for those who prioritise a ryokan with private onsen Nagano and a walkable riverside setting, this property represents a straightforward, authentic option.

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Highlights of this ryokan

Free parking
Family rooms
Free Wifi
Excellent Breakfast

Detailed Ratings

Staff 8.7
Equipements 8.1
Cleanliness 7.8
Comfort 8.1
Value for money 7.8
Location 8.1

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Review summary for: Kose Onsen

Positive Reviews

Secluded, peaceful mountain location

Ryokan is set in quiet mountains with beautiful scenery — streams and nearby waterfall hikes — making it a very relaxing, uncrowded retreat.

Excellent onsen options (private & public)

Guests praise both the public and private baths; the private rotenburo is free to use, very relaxing, well maintained and the water temperature is comfortable (one guest noted ~42°C).

Friendly, attentive staff

Staff are described as very polite, helpful and accommodating; although many speak little English they provide printed explanations and use translators to assist international guests.

Good traditional meals

Many reviewers highlight high-quality dinners (kaiseki-style) and authentic Japanese breakfasts — overall meals are considered a strong point by numerous guests.

Authentic retro ryokan charm

The property offers a nostalgic, well-preserved retro atmosphere with cozy rooms and traditional service (futon setup, meal call reminders), appreciated by guests seeking an authentic experience.

Negative Reviews

Remote location and limited transport

Property is remote — access by car is recommended. The bus service exists but is infrequent with early last departures, and mountain roads can be dark or difficult at night, which requires planning.

Cleanliness and maintenance concerns

Several guests reported issues such as mold/mildew spots in bathrooms, water damage, dust, stains and broken fixtures, indicating some areas need better upkeep.

Dated rooms and limited in-room amenities

Rooms and furnishings are described as tired or shabby by some; a few guests noted missing conveniences (e.g. no toiletries provided in-room, no hooks) and rooms that can be dark.

Uncomfortable bedding for some guests

Some visitors found the futons thin and the bedding relatively hard, leading to discomfort for those sensitive to firmer sleep surfaces.

Inconsistent food quality / value concerns

While many praise the dinners, a minority reported mediocre or poor meals and felt that, at times, price did not match quality — experiences with food quality varied between guests.

This summary is based on all online reviews and was last updated on 17 November 2025

Frequently Asked Questions

How many guests can stay in each room?

Room types include Japanese-style rooms and family rooms; some rooms accommodate up to four guests (quadruple/futon layouts). Please inform the hotel of the number and ages of children when booking.

Is the onsen natural and what are the public-bath hours?

The property uses its own natural springs (non‑recirculated) and the indoor baths are available from 13:00 until 10:00 the next day, with cleaning between about 10:00–13:00.

Can I reserve a private bath for my party?

Yes — there are two open‑air private (kashikiri) baths that fit up to four people; reservations are free and available while they are not in use (hours roughly 13:00–23:00 and 07:00–09:00).

Does the ryokan provide airport transfers or a shuttle?

The property does not advertise a regular airport shuttle; most guests arrive by car (free parking), taxi or local bus — contact the ryokan in advance if you need a pickup request.

How do I get to the ryokan from Karuizawa Station?

Kose Onsen is about a 15‑minute drive from JR Karuizawa Station; the simplest options are a taxi or the local bus (note bus service can be limited late at night).

What languages do the staff speak?

Staff primarily speak Japanese and English is limited; using a translation app or providing arrival details in advance is recommended.

What dining is available and do I need to book meals?

Breakfast and dinner (seasonal Japanese or Western menus, including the ryokan’s creative preparations) are offered but require prior reservation; guests should inform their arrival time since late check‑in may affect dinner service.

Are pets allowed and is the ryokan family‑friendly?

Pets are not permitted on the property; the ryokan is family‑friendly with family and multi‑person rooms, but you should notify the hotel of children and their ages before arrival.

Is there a nearby supermarket or shops?

The hotel sits in quiet hills, so the nearest supermarkets and larger shops are in central Karuizawa or at Karuizawa Prince Shopping Plaza (about a 20‑minute drive); plan to pick up supplies in town if needed.

What should I expect from the ryokan experience and onsen etiquette?

Expect traditional Japanese rooms, seasonal meals and a quiet mountain setting; observe onsen etiquette — wash thoroughly before entering, do not wear swimsuits in the baths, and check the ryokan’s tattoo policy or use a private bath if needed.

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