Overview
Introduction: What Is Modern Toji?
Tōji (湯治) is a Japanese tradition dating back centuries — the practice of staying at a hot spring for an extended period (days or weeks) to treat specific health conditions. Only Yu takes this concept and adapts it for the modern lifestyle, where a full day of intentional relaxation can provide many of the same benefits.
The philosophy is simple:
- Good water — alkaline hot spring water that softens the skin
- Time — stay from morning until evening (or overnight) without rush
- Environment — forest setting, natural light, quiet spaces
- Mindfulness — complimentary activities that encourage presence
Unlike a typical onsen where you might spend 1–2 hours bathing and leave, Only Yu encourages you to settle in. The entry fee includes a samue set (top and pants), towels, and access to all facilities. You can bathe, rest in the tatami lounge, read, meditate, eat, and bathe again — all in a single visit.
Why Choose Only Yu Over Other Hakone Onsen? Discover Mt Fuji’s 5th Station, World Heritage Center & Owakudani volcanic valley on this scenic Hakone day trip
| Only Yu | Typical Hakone Onsen |
|---|---|
| Samue included (wear all day) | Towel-only (change in/out) |
| Complimentary activities (zazen, calligraphy) | Bathing only |
| Forest setting, quiet atmosphere | Often crowded, tourist-oriented |
| Day trip + overnight both available | Most are either day or overnight |
| pH 9.5 alkaline (skin-beautifying) | Varied water quality |
| Free shuttle from station | Pay local bus |
The Hot Spring Water
Water Quality
Only Yu’s water is classified as alkaline simple spring (アルカリ性単純onsen (温泉, hot spring)). With a pH of 9.5, it is among the most alkaline hot springs in Kanagawa Prefecture.
Effects:
| Property | Effect |
|---|---|
| High alkalinity (pH 9.5) | Dissolves sebum and dead skin cells — leaves skin smooth |
| Low temperature (38–42°C) | Gentle on the body, safe for longer baths |
| Clear, odourless | No sulfur smell, comfortable for sensitive noses |
| Soft feel | Water feels silky on the skin |
Commonly described as: Bihada-no-yu (美肌の湯) — skin-beautifying hot spring.
Baths
Indoor Bath (大浴場):
- Large windows facing the forest
- Temperature: 40–42°C
- Separate men’s and women’s sections (rotating daily)
Outdoor Rotenburo (露天風呂):
- Surrounded by broadleaf trees
- Temperature: 38–40°C
- Natural light throughout the day
- Bird calls and rustling leaves create the soundscape
- Rotating gender schedule
Private Family Bath (家族風呂 / 貸切風呂):
- Available for reservation (additional fee)
- 45-minute sessions
- Indoor only
- Good for couples or small groups who prefer privacy
Facilities and Amenities
Samue Loungewear
Upon check-in, you receive a set of samue — the traditional Japanese clothing worn by monks and craftspeople. This is central to the Only Yu experience: changing into samue signals the transition from everyday life to relaxation mode.
The samue sets are available in multiple sizes, clean and pressed. You wear them throughout the facility — in the baths (before and after), in the restaurant, in the relaxation rooms. It eliminates the need to change between street clothes and bathing wear multiple times.
Kakure-za Relaxation Room
The Kakure-za (隠れ座) is a large tatami room where guests can lie down, nap, read, or simply stare at the ceiling. Low ambient lighting, the scent of tatami, and distant forest sounds create an atmosphere that encourages genuine rest.
Etiquette:
- Keep voices low (others may be sleeping)
- No phones on speaker mode
- Shoes off before stepping onto tatami
- Photography allowed but be mindful of others
Library Corner
A small collection of books (mostly Japanese) about hot springs, wellness, and nature. The selection changes seasonally. Digital detox is encouraged — the library corner has limited mobile reception.
Suhari Cafe
The on-site cafe serves light refreshments:
- Matcha and coffee sets (¥500–700)
- Seasonal desserts (¥600–800)
- Soft drinks and fresh juice (¥400–500)
Yururi Restaurant
The buffet restaurant focuses on healthy, vegetable-forward Japanese cuisine:
| Meal | Time | Price | Notes |
|---|---|---|---|
| Lunch buffet | 11:30–14:00 | ¥1,800 | Local vegetables, seasonal dishes |
| Cafe menu | 14:00–17:00 | ¥500–1,000 | Light snacks and drinks |
| Dinner (overnight guests) | 18:00–20:00 | Included | Kaiseki-style course |
Complimentary Activities
Only Yu offers a selection of free activities designed to complement the hot spring experience. These are included in the entrance fee.
Zazen (Sitting Meditation)
- Schedule: Daily, morning session (30 min)
- Location: Dedicated meditation space
- Instructor: Staff-guided (beginner-friendly)
- Language: Japanese with basic English guidance
- What to expect: Simple sitting meditation, no special clothing required
Japanese Calligraphy (Shodo)
- Schedule: Afternoon sessions (45 min)
- Materials: All provided
- What to do: Practice basic brush strokes, write your favorite kanji
- Take-home: Your work becomes a souvenir
Stretching and Relaxation Class
- Schedule: Morning and afternoon (20 min)
- Focus: Gentle stretches suitable for all ages and fitness levels
- Location: Kakure-za room or outdoor deck (weather permitting)
Seasonal Activities
| Season | Activity |
|---|---|
| Spring | Forest walking guide (cherry blossom route) |
| Summer | Evening cooling deck (outdoor relaxation) |
| Autumn | Leaf-peeping walk (maple route) |
| Winter | Indoor tea ceremony demonstration |
Day Trip vs Overnight
Day Trip Plan
| Time | Activity |
|---|---|
| 10:00 | Arrive, check in, change into samue |
| 10:30 | Morning bath (rotenburo) |
| 11:30 | Zazen session (if available) |
| 12:00 | Lunch at Yururi buffet |
| 13:00 | Kakure-za rest / reading |
| 14:00 | Calligraphy workshop |
| 15:00 | Afternoon bath (indoor) |
| 16:00 | Cafe break at Suhari |
| 17:00 | Final bath before closing |
| 18:00 | Change back, depart |
Day trip fee: ¥2,500–3,500 (varies by season)
Includes: Samue, towels, all facilities, activities
Overnight Stay
Overnight guests can check in from 10:00 AM and stay until 12:00 PM the next day — up to 35.5 hours of relaxation.
Overnight fee: ¥15,000–25,000 per person (varies by season and room type)
Includes: Day trip access + dinner + breakfast + futon accommodation
Some rooms include a private indoor bath with the same alkaline water — a worthwhile upgrade for couples or those seeking complete privacy.
Practical Information
Fees
| Plan | Adult | Child (4–12) |
|---|---|---|
| Day trip (weekday) | ¥2,500 | ¥1,200 |
| Day trip (weekend/holiday) | ¥3,500 | ¥1,700 |
| Overnight (per person) | ¥15,000–25,000 | Varies by plan |
| Private bath (45 min) | ¥2,000 | — |
Hours
| Day | Hours | Last admission |
|---|---|---|
| Daily | 10:00–21:30 | 20:00 |
What to Bring
Provided (included in fee):
- Samue (loungewear, top and pants)
- Large towel and face towel
- Sandals
- Lockers (coin-operated, refundable)
Recommended to bring:
- Hair ties (long hair must be tied up in baths)
- Moisturiser (alkaline water can be drying after prolonged bathing)
- Small change for lockers (¥100 coin, refundable)
- Book or journal (for the Kakure-za room)
- Water bottle (hydration is important)Rules and Etiquette
Do's:
✅ Wash thoroughly before entering any bath
✅ Tie up long hair before entering the water
✅ Use the small towel for drying (never dip it in the bath)
✅ Speak quietly in relaxation areas
✅ Enjoy the samue throughout the facility
Don'ts:
❌ No tattoos (Japanese onsen policy — cover with patches if small)
❌ No photography in bathing areas
❌ No swimwear in the baths
❌ No infants with diapers in the water
❌ No food or drinks in the bath area
❌ No phones in the Kakure-za roomWhen to Visit
Best for solitude: Weekday mornings (before 12:00 PM)
Best for atmosphere: Autumn weekdays (colorful leaves)
Best for budget: Weekday day trips
Avoid: Weekend afternoons (busiest), national holidays
Seasonal recommendation: Autumn (forest colors + outdoor bath)Frequently Asked Questions
Q: Is Only Yu suitable for people with tattoos?
A: Like most Japanese onsen, Only Yu does not permit tattoos in the bathing areas. Small tattoos can be covered with waterproof patches (available at the front desk). If you have large or multiple tattoos, consider reserving a private family bath instead.
Q: Can I visit as a same-sex couple?
A: Yes. The baths are gender-separated (rotating schedule), but the Kakure-za relaxation room, restaurant, and cafe are co-ed spaces. Same-sex couples can enjoy all shared areas together.
Q: Is English spoken at the facility?
A: Basic English is understood at the front desk. Signage has some English. The zazen and calligraphy sessions are conducted primarily in Japanese but are visual enough for non-speakers to follow.
Q: Do I need to book the shuttle in advance?
A: Yes — the free shuttle requires a reservation made at least 24 hours in advance. Contact the facility by phone or through their website.
Q: Can I bring my own food?
A: Outside food and drinks are not permitted. The Yururi buffet and Suhari cafe cover all dining needs.
🌟 Share Your Experience
Visited Only Yu? Tips for combining it with a Hakone day trip? Join our community forum to share your experience!
Only Yu is not the most famous onsen in Kanagawa, and that is precisely its appeal. It offers something increasingly rare in Hakone’s crowded hot spring landscape: genuine silence, space to breathe, and water that rewards slow soaking. Whether you visit for a day of modern toji or an overnight stay with private bath, the experience is defined not by what you do, but by how long you allow yourself to do nothing at all.
For more onsen options in the region, read the Hakone onsen complete guide, the Hakone day trip onsen guide, or the broader Kanagawa onsen guide.
⏰ Best Time to Visit
Early morning (8–10 AM): Peaceful atmosphere, fewer crowds, perfect for photos Late afternoon (4–6 PM): Beautiful lighting, local life, less crowded than midday
🎯 What I Recommend
- Don’t rush: Take your time to explore the side streets and hidden spots
- Talk to locals: They often know the best lesser-known spots that aren’t in guidebooks
- Try the local specialties: Each area has its own unique food and souvenirs
⚠️ Things to Watch Out For
- Some shops close on weekdays or have irregular hours
- Parking can be challenging during peak seasons
- Cash is still king at many smaller establishments
- Cash: Still preferred at smaller establishments and ramen shops Make your own ramen from scratch at Ramen Dojo Tokyo — a fun hands-on cooking experience
Conclusion
The details in this guide come from real visits, and the biggest lesson I took away was that the best experiences in Hakone rarely fit neatly into a checklist. During my visit to Hakone I went with a rough plan and found that leaving room to wander made the trip far more memorable. Plan the essentials, keep your schedule flexible, and you will leave Kanagawa wanting to return.
Guide 2026