Overview

Kobo no Yu Nagaoka is a hot spring and bathing retreat in Izunagaoka Onsen, Shizuoka. You come here for a strong focus on toji-style bathing, where the stay centers on soaking, warming the body, resting, and repeating the rhythm at your own pace.

The property uses three private hot spring sources and combines flowing hot spring water with natural radium ore spaces using Hokutoite and Bad Gastein ore. You can stay overnight, visit for the day, use the bedrock bath, relax in the mist sauna, book the private sauna, and enjoy simple meals at the in-house dining room. The atmosphere is practical and wellness-focused, making it a good choice when bathing is the main reason for your stay.

Accommodation

Kobo no Yu Nagaoka offers Japanese-style rooms in the main building, annex rooms with indoor baths, annex rooms with mini open-air baths, and special rooms with semi-open-air baths. The main building and annex rooms are all Japanese-style, giving you a tatami space where you can stretch out, rest, and keep the mood simple.

The standard Japanese rooms range from compact 30-square-meter rooms to larger 42-square-meter and 60-square-meter layouts. These rooms suit you well when you want a straightforward toji stay focused on the baths and wellness facilities. The twin-bed Japanese room gives you two connected Japanese-style rooms with beds, so you can enjoy tatami space without sleeping on futons.

The annex rooms add more private bathing comfort. Some include indoor baths, while others include mini open-air baths. The semi-special room has an open-air bath and a Japanese-style layout, while the special room has two Japanese rooms and a semi-open-air bath. These room types work well when you want more privacy during your stay.

The property also has Villa Bettei Siki, four detached villa rooms themed around spring, summer, autumn, and winter. Each villa includes a hinoki flowing open-air bath, indoor bath, private BBQ space, and ReFa items in the bathroom and powder room. The autumn villa can be used with a dog and includes a private dog run.

All main building, annex, and special rooms include a washbasin, washlet toilet, refrigerator, flat-screen television, and kettle. Futon setup is self-service, so you can prepare your sleeping space when you are ready. The building is non-smoking, with smoking spaces in the first-floor courtyard and on the second floor.

Dining

Dining is served at Shokujidokoro Kuukai on the second floor. The food is warm, familiar, and easy to enjoy, with seasonal ingredients, local vegetables, and fresh seafood used in the meals. You can eat breakfast, lunch, or dinner here, depending on your plan and schedule.

Dinner plans include standard dinner, a higher-grade chef’s selection dinner, and the property’s highest-grade dinner course. Meal content changes by season, so you can enjoy dishes that match the time of year. Some plans also allow dinner to be delivered to your room, giving you a more private and relaxed way to eat after bathing.

If you stay without meals or book breakfast only, you can still use the dining room for casual dishes. You may find set meals such as sashimi, udon, soba, tororo, and simple à la carte dishes. In-room dining is also available for overnight stays during set hours, with light meals, snacks, and desserts that work well when you want something after your bath.

Breakfast is served in the morning at Kuukai, and rice options may include white rice or rice porridge. Children’s meals are available for dinner and breakfast, with different styles for younger children and elementary-age children.

Onsen and Wellness

The main reason to stay at Kobo no Yu Nagaoka is the bathing. The property has three hot spring sources and uses Hokutoite and Bad Gastein ore throughout its wellness spaces. The shared baths include flowing radium-style hot spring bathing, with Hokutoite placed beneath the hot spring outlet so the water passes over the ore before entering the bath.

The flowing radium-style bath uses water that is not circulated from the outlet. The water is kept at a gentler temperature of around 38.5°C to 40°C, so you can soak longer and relax without feeling overheated too quickly. There is also an open-air bath where you can enjoy the outdoor air between rounds of bathing.

The bedrock bath is used while wearing yukata. You lie on warm granite beds heated by hot spring water, with Bad Gastein ore in the floor and hot spring water passed through Hokutoite used to raise the humidity. The bedrock bath has 62 beds across separate men’s and women’s areas, giving you space to sweat, rest, and warm the body slowly.

The medicinal stone mist sauna uses granite beds, Bad Gastein ore flooring, and mist made from hot spring water that has passed through Hokutoite. It is a lower-temperature sauna, around 38°C to 41°C, so it feels gentler than a dry sauna while still encouraging deep sweating. The property also has a stone therapy room where you can rest on reclining chairs and Bad Gastein beds after bathing.

The private sauna adds another wellness option by reservation. It includes a Finnish sauna heater, a source-flowing hinoki hot spring bath, cold-water bath, shower, and rest chairs. This gives you a more private way to enjoy sauna, hot spring bathing, cooling down, and rest in one space.

Guests with Tattoos

Kobo no Yu Nagaoka does not accept entry if you have tattoos, including small one-point tattoos. This applies to use of the property, not only the shared bathing areas.

Facilities

Kobo no Yu Nagaoka has shared hot spring baths, an open-air bath, bedrock bath, medicinal stone mist sauna, private sauna, stone therapy room, day-use rest room, Shokujidokoro Kuukai, lobby, souvenir corner, vending machines, coin laundry, smoking spaces, karaoke rooms, changing rooms, banquet rooms, free massage chairs near the rest area, zero-gravity massage chairs near the shop, and a relaxation salon called Riraku. The lobby displays Hokutoite from Tamagawa Onsen in Akita and Bad Gastein ore from Austria, along with information about their history. The souvenir corner sells bath items, local products, sweets, hot spring manju, and drinks.

The coin laundry is located on the third and fifth floors of the main building. The day-use rest room can be used during the day-use bathing hours, while the banquet rooms and karaoke-equipped spaces can be used for group meals and gatherings. The private sauna is reservation-only and includes towels, yukata, and drinks in the room’s refrigerator.

Activities

You can spend most of your time inside the property, moving between the hot spring bath, bedrock bath, mist sauna, stone therapy room, private sauna, dining room, rest areas, and massage spaces. This works well when you want a health-focused stay where the main activity is bathing and resting.

You can also explore Izunagaoka and the surrounding Izu area. The property is close to the Izunagaoka Onsen area, and nearby sightseeing includes Izunokuni Panorama Park, Izu Mito Sea Paradise, and other local spots around Izunokuni and the Izu Peninsula. From the hotel, it is also easy to continue toward Shuzenji, Mishima, or the wider Izu region.

Additional Features

Kobo no Yu Nagaoka gives you three private hot spring sources, flowing radium-style hot spring bathing, Hokutoite and Bad Gastein ore wellness spaces, bedrock bathing, medicinal stone mist sauna, a stone therapy room, private sauna, Japanese-style rooms, rooms with private baths, detached villa rooms, in-house dining, day-use bathing, rest spaces, coin laundry, banquet rooms, karaoke rooms, and on-site relaxation services.

Check-in is from 15:00, with early check-in available from 12:00. Check-out is by 10:00. The baths for overnight stays are available from 5:00 to midnight, while day-use bathing is available from 6:00 to 23:00, with final reception at 22:00.

The property is located at 1110 Nagaoka, Izunokuni, Shizuoka. From Mishima Station, take the Izuhakone Railway to Izunagaoka Station, then continue by taxi in about six minutes. By bus, get off at Onsen Station, which is about 30 seconds on foot from the property.