Asama Onsen, Matsumoto, Nagano Prefecture
Hot Plaza Asama
A dependable first choice if you want a sauna, an evening soak, an easy bus connection or confirmed tattoo access. For the earliest and cheapest bath, choose Senki-no-Yu; for a historic garden setting, choose Biwa-no-Yu.
Check before bathing
- Opening hours
- 10:00–24:00; last admission 23:00. Closed Tuesdays, or the following day when Tuesday is a public holiday.
- Access
- A bus stop is located in front of the facility.
- Tattoo policy
- Permitted. The facility's official Traditional Chinese page explicitly says guests with tattoos may use the baths.
Spring & water temperature
- Spring-source temperature
- 49.7°C, for the blended supply system described by the facility.
- Bathing temperature
- Not published.
- Spring source
- A blended supply from the Asama Onsen system; individual wells are not named for this facility.
- Spring classification
- Weakly alkaline simple hot spring; colourless and clear.
- pH
- Not published.
- Flow rate
- 815 L/min, measured for the blended supply system rather than a single well.
- Water handling
- The facility says about 26 tonnes of spring water are supplied each day. Water is added and heated for temperature control, then circulated through filtration for hygiene management. The footbath in front of the building is described as source-flowing; that does not establish the same supply method for the main baths.
Bathing indications
The facility lists general hot-spring bathing indications. These are not a medical or treatment guarantee.
The facility says water is added and heated for temperature control, then recirculated through filtration for hygiene management.
Current adult admission is ¥750; elementary and junior-high students are ¥400, and preschool children are free. Tattoos are permitted according to the facility's own Traditional Chinese page.
How to read a bath profile
Spring-source temperature and actual bathing temperature are kept separate. Each score is shown independently for comparison rather than collapsed into one overall score.
