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Hot Springs

【Two types of hot springs】1. Hotaru Onsen under the starry sky, surrounded by dancing fireflies.

Hotaru Onsen is a hot spring resort Shiga Highlands, the center of Joshinetsu-Kogen National Park, located upstream of the Kakuma River that runs between Mt Kasagatake and Mt Yokote
Hotel Onsen 2307 Shigakogen Mt Yokote
Surrounded by mountains at an altitude of 2,000 m and mysterious ponds and swamps, the beautiful Shiga Highlands is truly a treasure trove of nature.
In the surrounding area, the altitude of firefly outbreak is the highest in Japan, and the landing period of larvae and the outbreak period of adults are the longest in Japan.
It is also famous as a habitat for Genji firefly, a natural monument known for its long lifespan.
It is said that the name "Hotaru Onsen" is derived from this place, and you can enjoy it from mid-July to mid-August.
If you soak in the hot water in a fantastic space where you can dance while looking up at the starry sky, you will gradually feel calm.

【2,000m above sea level】Hot springs where fireflies and stars dance

The view and mood are great.Relax your body and soul in the effective natural hot spring "Hotaru Onsen".
You can take a bath 24 hours a day, so you can take a bath at any time you like.
  • "1F" Separate open-air bath(Sulfur spring cloudy water)

    The hot spring in the open-air bath has been renewed to a cloudy hot spring!

    The water has changed from clear spring water to cloudy sulfur spring water.
    This milky sulfur spring changes color from cloudy white to cloudy green to clear green depending on the temperature and humidity!

    What color will it be when customers come in?

    The open-air baths are still available free of charge to guests staying at the hotel, so anyone can use them at any time without making a reservation!

    Tsukishiro-no-yu (men's bath) and Hanaba-no-yu(Women's bath)

    Hot spring bath hours
    From 14:00 to 10:00 the next morning(Simple cleaning time zone Midnight 1:00 to 3:00)
    Hot spring bathing category
    Men's bath/Women's bath (Cypress bath,Stone bath 1 each)
    Hot spring qualities
    Mt Yokote Onsen (Spring quality: Cloudy sulfur spring, 100% natural hot spring) Free flowing from the source*Does not include artificial hot springs
    It is a milky sulfur spring, and the color of the water changes from cloudy white to cloudy green to transparent green depending on the time, temperature, and humidity.
    What color will it be when you come in?
    That's part of the fun.

    Peripheral circulatory disorders
    Sensitivity to cold
    High blood pressure(Mild)
    Impaired glucose tolerance(Diabetes)
    Gastrointestinal dysfunction
    Rheumatoid arthritis
    Autonomic instability
    Chronic pain and stiffness in muscles and joints
    Muscle stiffness due to motor paralysis
    Atopic dermatitis
    Psoriasis vulgaris
    Chronic eczema
    Skin suppuration
    Hemorrhoid pain
    Recovery period
    Relieve fatigue and improve health
    1. There is no washing area.
     Please use the indoor bath in this facility before using the open-air bath.
     *Shampoos cannot be brought in

    2. Previously, it operated as a private bath for a small number of people on an hourly basis, for which a fee was charged.
    Currently, it is free to use, but it fills up when there are around seven people.
    If it is crowded, please use it at a different time.

    3. It is a hot spring where it is easy to get sick from the bath
    Sulfur springs have a high penetration effect on the skin, and are said to be the hot springs that are most likely to cause skin irritation out of all the other springs.

    4. Be careful of rough skin
    The strong antibacterial properties of sulfur springs can be very irritating to the skin, so if you have sensitive or dry skin, it may cause irritation to your skin.

    5. Metal products may turn black
    The hydrogen sulfide contained in sulfur springs oxidizes metals, causing them to turn black.
    Please be careful not to bring any metal items such as earrings, rings, necklaces, watches, glasses, etc. into the hot springs.
    It may even discolor if it comes into contact with steam.
    Usage fee
  • 【4F】Observation bath(transparent simple spring)

    Please enjoy a relaxing and enjoyable time while watching the changing atmosphere of the four seasons.
    Hot spring bath hours
    From 14:00 to 10:00 the next morning(Simple cleaning time zone Midnight 1:00 to 3:00)
    Usage fee
  • About hot springs

    【Source name】Kumanoyu Hiratoko-no-yu
    【Source】Simple hot spring(Neutral hypotonic high hot spring)
    【Source temperature】Source 55.5℃ Usage position
    【Diseases and symptoms that are good to take a bath】Neuralgia/muscle pain/Joint pain/Fifty shoulders/Motor paralysis/Joint stiffness/Bruise/Kujiki/Chronic digestive disease/Hemorrhoids/Sensitivity/Post-illness recovery period/Fatigue recovery/Health Promotion

Hot spring information

Hot Springs

Hotaru Onsen (100% natural hot spring) Hot spring flowing*Does not include artificial hot springs

Open Air Bath

Men's bath/Women's bath

Number of baths

[Open-air bath]Man:1 woman:1
[Indoor bath]Man:2 female:2 Mixed bathing:0
[sauna]Man:0 woman:0 Mixed bathing:0

Hot spring tax

Will be charged separately.
Adult(s):150 yen/Children(0-11 years old):Free

Source name

Kumanoyu Hiratoko-no-yu


Simple hot spring(Neutral hypotonic high hot spring)

Source temperature

Source 55.5℃ Usage position

Diseases and symptoms that are good to take a bath

Neuralgia/muscle pain/Joint pain/Fifty shoulders/Motor paralysis/Joint stiffness/Bruise/Kujiki
Chronic digestive disease/Hemorrhoids/Sensitivity/Post-illness recovery period/Fatigue recovery/Health Promotion

Bathing time

Bath available 24 hours
(Cleaning time 10:00 to 12:00,Midnight 1:00 to 3:00)