Onsen with a sauna in Gunma

Kusatsu · Multiple reviewers from August and July 2026 confirm sauna is available.

Takasaki · Recently renovated sauna facilities with two rooms (auto-loyly and self-loyly), widely praised.

Annaka · A sauna is confirmed by several reviewers.

Numata · A dry sauna (around 94C, 6-person capacity) is available.

Ota · Multiple sauna types including a barrel sauna and a Mongolian-style sauna, well regarded overall though loyly (steam pouring) is currently banned in the barrel sauna.

Shibukawa · Dry sauna present with temperature around 80°C+, capacity ~10 people; small but functional.

Numata · Sauna is confirmed by several reviewers, though one notes it gets very crowded (5 people packed in).

Shibukawa · Multiple reviews confirm sauna availability; one review reported 97°C in early summer.

Maebashi · Multiple sauna types exist (dry ~90C sauna, steam sauna, stadium sauna) with occasional löyly service.

Maebashi · A sauna is available alongside jet bath, jacuzzi, and cold bath.

Minakami · Facility has a Bona sauna (Finnish-style with specific design); indoor temperature approximately 86°C, not extremely hot.

Katashina · A sauna running around 95C is available, small (about 6 person capacity).

Shibukawa · Sauna available; weekends have 3-hour time limit for sauna access; swimwear required per staff (not posted on website).

Shibukawa · Sauna is present but small; one visitor noted perceived temperature is lower than the thermometer indicates, and a cold bath is not available.

Maebashi · A sauna is available and well-regarded, with good temperature and a water fountain nearby.

Takasaki · A sauna is available alongside the baths, confirmed by several reviewers.

Isesaki · Facility has two sauna rooms, mentioned across four reviews.

Shibukawa · Guest rooms include saunas with aroma treatments; sauna with water treatment available.

Isesaki · A large L-shaped high-temperature electric sauna seating 10+ people, mentioned repeatedly and positively.

Takasaki · An outdoor sauna (roughly 90C, 18-person) with TV is present, though it lacks sauna mats on some visits.

Ota · A far-infrared two-tier sauna plus a low-temp salt steam room are described by several reviewers.

Tomioka · A small sauna (fits about 5-8 people) is available and generally well-liked.

Annaka · A sauna is present, though descriptions vary between a small dry sauna near 90C and a mist sauna.

Maebashi · Two sauna types are available (dry sauna and steam/mist sauna).

Yoshioka · Three sauna types are available: high-temperature, medium-temperature, and steam/mist.

Maebashi · The sauna (including a salt sauna) is spacious and well-regarded, though it is also where regular-customer conflicts most often occur.

Isesaki · Several reviews describe multiple sauna rooms (dry sauna, löyly-style sauna) as a highlight.

Shibukawa · Small sauna in communal bath on 1st floor with ladle for löyly.

Yoshioka · Has a sauna, though regulars often occupy it.

Maebashi · A sizeable sauna (10-20 person capacity) with TV is repeatedly confirmed, generally with auto-rolyu steam.

Kiryu · A self-service loyu (water-on-stones) sauna is popular with reviewers.

Tsumagoi · Communal sauna present; multiple visitors report it is warm and spacious, though some note low temperature (70–75 °C) in 2026.

Takasaki · A stove-heated sauna up to 96C with daily löyly sessions and a TV.

Minakami · Low-temperature sauna (around 70°C) in communal bath area; far-infrared sauna mentioned by one visitor.

Shimonita · A sauna is present, though it was reported closed during the COVID period around 2020-2022.

Takayama · A sauna is available.

Maebashi · A sauna is consistently reported (80-90°C), though reviewers disagree on whether it feels small/cramped or large.

Numata · A large multi-tier sauna, reported temperatures roughly 80-100C, is a highlight of the facility.

Numata · Both a regular high-heat sauna and a weekend-only cypress-lined salt sauna are offered.

Kiryu · A dry sauna and an outdoor loyly (steam) sauna are both available, along with a paid private sauna room.

Ota · A sauna is confirmed by many reviewers.

Annaka · A sauna exists but only operates weekends/holidays and shuts off as early as 17:00-18:00; one reviewer measured a low 76-78C and warned the resulting cold-plunge shock could be risky for elderly visitors.

Showa · A small sauna is mentioned by several reviewers, though it can be dominated by regulars and mismanaged etiquette.

Shibukawa · Sauna present; one review (2025-09) noted it was not operating at time of visit.

Ota · A sauna is available.

Numata · A small dry sauna is on site, frequently described as cramped (fits only 2-3 people).

Minakami · Mist sauna with the spring water is available in the communal bath area; visitors describe it as producing moisture and lasting 15 minutes.

Numata · Sauna is confirmed by many reviewers.

Maebashi · A sauna is available.

Minakami · Sauna available; wood-fired sauna is reservation-only and generates significant smoke during operation.

Ota · The facility has a small dry sauna (around 70C, five-person capacity), though it has been out of order on at least one visit.

Shibukawa · Sauna present but extremely cramped (capacity 3–5 per row across 2 tiers); visitors consistently report tight squeeze and poor temperature management.

Katashina · A large sauna reaching roughly 93-100C is present, though some reviewers find it not very hot.

Tsumagoi · Communal sauna available.

Midori · A sauna with automatic loyly (steam bursts), capacity around 10, running 96-98°C.

Shibukawa · The adjacent hotel's communal bath includes a sauna (2025-09, 2026-05).

Nakanojo · Steam-room-style saunas (steam bath chambers) present; described variously as small closet-like spaces with steam or humidity; reviews 2020–2026.

Naganohara · A sauna (and mist sauna) is available, confirmed by several reviewers.

Katashina · Has a sauna, though one reviewer found it old and left quickly.

Minakami · Facility has sauna; women's area includes mist sauna and low-temperature sauna.