Saitama · Kumagaya
Kumagaya Hanayu Spa Resort
熊谷天然温泉 花湯スパリゾート
One of the largest spa complexes in Saitama, in Kumagaya in the north of the prefecture. Its own alkaline simple spring, pumped from 1,500 m at over 600 litres a minute, feeds a wide range of tubs — a free-flowing open-air 'raw source' bath, pot baths, lie-down baths and a high-concentration carbonated bath. There is a löyly sauna, cold plunge and a garden-view outdoor rest deck. The optional 'Onkatsu Café Nest' adds eight kinds of bedrock-bath rooms, manga and free drinks for an all-day stay. Admission ¥950 on weekdays, ¥1,100 on weekends and holidays; open 10:00–23:00 (last entry 22:30), no closing days. Private rooms with an open-air pot bath can be reserved by phone. About 10 minutes by bus or taxi from JR Kumagaya Station; 300 free parking spaces. Kumagaya is about 40 minutes from central Tokyo by Shinkansen — combine with rugby at the stadium or Menuma Shōdenzan temple.
- Price (adult)
- ¥800
- Hours
- 10:00–23:00 (last entry 22:30)
- Closed
- Open daily (closes for maintenance)
- Access
- Local bus from the south exit of JR Kumagaya Station to the 'Hanayu Spa Resort' stop, or about 10 min by taxi; about 30 min by car from Higashi-Matsuyama IC
- Water type
- Alkaline simple
- Tattoos
- Not allowed
- Admission
- Bathing: adults (junior high and up) ¥800 weekdays / ¥980 weekends and holidays; children (elementary and under) ¥450 / ¥550 (5-hour limit on weekends and holidays, surcharge beyond). 'Onkatsu Cafe NEST' (bedrock bath, loungewear and towel set) +¥650–700 weekdays / +¥750–800 weekends (junior high and up; sofas, 10,000 manga, Wi-Fi). Towel set ¥200, loungewear ¥200. Private rooms from ¥3,800 for 2 hours. Restaurant 'Iroha-no-i' (udon, set meals), body care and scrubs. Shampoo provided. Lockers free. Tattoos not permitted (check rules)
- Baths
- A natural hot-spring super-sento in Kumagaya, northern Saitama (opened 2018), billed as the Kanto region's largest 'onkatsu cafe'. Water from 1,500 m underground fills over ten baths — an open-air free-flowing source pool, high-concentration carbonated bath, cypress bath, hot bath — plus a tower sauna (100°C-plus, auto-loyly) and a large plunge pool popular with sauna fans. Five bedrock-bath rooms and the 'NEST' lounge with 10,000 manga. Known as a summer refuge in Kumagaya, 'Japan's hottest town'. Near Kumagaya Rugby Stadium and the Sakura-tsutsumi cherry embankment
- Spring water
- Kumagaya Onsen, a strong sodium-chloride spring (hypertonic, neutral, about 39°C at source, abundant flow). Light-to-dark brown 'fossil seawater' type, strongly salty and extremely heat-retaining — a 'heat bath'. The open-air free-flowing pool is unheated and unrecirculated, tepid at 38–39°C and suited to long soaks. Indicated for poor circulation, neuralgia, muscle pain, cuts and dry skin. The high-concentration carbonated bath (artificial) boosts circulation
- Access & parking
- Free shuttle bus about 15 min from the north exit of Kumagaya Station (JR Takasaki Line / Joetsu Shinkansen; 1–2 an hour, check the timetable) or 10 min by taxi (about ¥1,500); 20 min on foot from Ishiwara Station on the Chichibu Railway. About 1 h 10 min from Tokyo (Ueno) by Takasaki Line rapid, 40 min by Shinkansen. By car 25 min from Hanazono IC (Kan-etsu) or 30 min from Kazo IC (Tohoku), near the Route 17 Kumagaya bypass. Free parking for 300
- Phone
- 048-501-1126
- Official site
- hanayu-spa.jp ↗
- Open in Google Maps
- Google Maps ↗
Essentials
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Why go
- Saitama's biggest spa, free-flowing source bath
- Carbonated bath, löyly sauna, outdoor rest
- All-day stay with 8 bedrock-bath rooms
Brown free-flowing source water and the Kanto region's largest 'onkatsu cafe' in Japan's hottest town
Kumagaya Natural Hot Spring Hanayu Spa Resort is a large natural-hot-spring super-sento opened in 2018 in Kumagaya, northern Saitama — 'Japan's hottest town', holder of the national record high of 41.1°C. Water from 1,500 m down is a light-brown strong chloride spring of the salty, heat-retaining 'fossil seawater' type, and the open-air 'free-flowing source bath' lets the tepid 38–39°C water run through unheated and unrecirculated, so that, unusually for an urban facility, connoisseurs can enjoy a 'real onsen' at length. There are also more than ten tubs — high-concentration carbonated, cypress, hot and reclining baths — plus a 100°C-plus tower sauna with auto-loyly, a wide, deep plunge and an outdoor cool-down area that sauna fans call 'the strongest in northern Saitama', while the five bedrock-bath rooms and the 'Onkatsu Cafe NEST' lounge with 10,000 manga, sofas and Wi-Fi keep many guests for the whole day. Bathing alone is a reasonable ¥800 on weekdays and ¥980 on weekends and holidays (5-hour limit), and the NEST surcharge adds bedrock baths, loungewear and towels. Fifteen minutes by free shuttle from Kumagaya Station and a little over an hour from Tokyo, it serves as a northern-Kanto day spa, is often paired with matches at Kumagaya Rugby Stadium, the Sakura-tsutsumi cherry blossoms or the Kumagaya Uchiwa Festival (July), and fills with people escaping the heat in summer.
Tepid free-flowing source, tower sauna, then a day at NEST
Put your shoes in the entrance lockers, choose bathing or the NEST set at reception and receive a locker-key band; all in-house charges are settled on exit (5-hour limit on weekends and holidays, surcharge beyond). Indoors are a high-concentration carbonated bath (37–38°C; bubbles cling to the skin after ten minutes), cypress, hot and jet baths; outdoors the light-brown 'free-flowing source bath', a heated hot-spring pool, a reclining bath and pot tubs. The recommended order: wash, then go straight to the open-air source bath. The tepid 38–39°C brown water tastes salty and seems 'lukewarm' at first, but after 15–20 minutes it heats you from the core and you keep sweating long after — the true worth of a chloride spring. Then the tower sauna (tiered seating, about 100°C at the top, auto-loyly on the hour), a deep 16–17°C plunge and a rest on the outdoor chairs — three rounds is the sauna-lover's standard; chairs are easy to find on weekday afternoons but fiercely contested on weekend evenings. The bedrock baths (NEST) comprise five rooms of differing temperature and a cool room, after which many stretch out on recliners and sofas in the lounge with its 10,000 manga or work on the Wi-Fi — good for half a day. The restaurant 'Iroha-no-i' is known for Musashino udon, set meals, beer and shaved ice in summer. Crowds peak 14:00–20:00 on weekends, sometimes with entry queues, so right at opening or after 8 p.m. on weekends, or weekday afternoons, are most comfortable. The shuttle runs only once or twice an hour, so check the last departure, and note that tattoos are not permitted.
Practical details and a Kumagaya / northern-Saitama route
Hours are 10:00–23:00 (last entry 22:30), open year-round (a few maintenance closures a year announced on the official site); bathing ¥800 weekdays / ¥980 weekends and holidays, children ¥450/¥550, NEST set +¥650–800, towel set and loungewear ¥200 each, free parking for 300. Access is the free 15-minute shuttle from the north exit of Kumagaya Station (check the timetable) or 10 minutes by taxi; 25 minutes by car from Hanazono IC. Suggested routes: (1) a Tokyo day trip — Takasaki Line from Ueno (1 h 10 min), stroll Kumagaya's castle site, Shodenzan Kangi-in temple and Hoshikawa street, lunch on 'Yukikuma' shaved ice (the summer speciality) or inari-zushi, the whole afternoon at Hanayu, then home; (2) rugby and sport — a soak after a match at Kumagaya Rugby Stadium (home of the Wild Knights) or the Sports and Culture Park; (3) blossom and festivals — the 2 km Sakura-tsutsumi embankment (late March–early April) then Hanayu, or the Kumagaya Uchiwa Festival on 20–22 July (one of Kanto's largest float processions) followed by a night bath; (4) with Chichibu — Nagatoro river boats and Chichibu Shrine by Chichibu Railway, back to Ishiwara or Kumagaya for Hanayu; (5) winter — Fukaya leek dishes and Fukaya Station (model for Tokyo Station), then Hanayu. Children's rates are low, but NEST and the bedrock baths are for junior high and up, and the weekend 5-hour limit incurs a surcharge, so watch the clock. Northern Saitama has other natural-spring super-sento — Gyoda's 'Kodai Hasu Monogatari', Honjo's 'Yura-no-sato' — that make for fun comparison.
Before you go
- Tattoos are explicitly not allowed, even if covered.
- Payment is usually by ticket machine in cash — bring coins.
- Last entry is 30–60 minutes before closing.
Features
Sauna & wellness
Rules & private
Who with
Price
Amenities
✔ Verified operating: 2026-09 Operating status and rates cross-checked against the official site and onsen guides (full source notes in Japanese on the JA page)
Prices and hours change. Check official sources before visiting.
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Chichibu Onsen Mangan no Yu
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