Kusatsu Onsen Yumomi: 300 Years of Hot Spring Culture

"Yumomi" is a distinctive bathing culture handed down since the Edo period at Kusatsu Onsen, the celebrated hot spring in Gunma Prefecture. Kusatsu's source water is so hot that it exceeds 50 degrees Celsius, and to avoid spoiling the water's medicinal properties the temperature had to be lowered without diluting it with cold water. What emerged was "yumomi": stirring the water with long boards so that it meets the air and cools. The traditional sight of the boards being worked in time to yumomi songs is now one of the emblematic attractions of Kusatsu Onsen. Here the wisdom and culture unique to Kusatsu, which boasts one of the largest natural spring flows in Japan, are still very much alive.

The Wisdom of Cooling a Famously Hot Spring

The reason Kusatsu Onsen developed its own culture of "yumomi" lies in water that is extremely hot, strongly acidic and rich in medicinal properties. In order to make full use of the precious components of the source water just as they are, yumomi was devised as a way of lowering the temperature without adding water. Using large boards about 1.8 metres long and stirring the water together in time as a group, the scalding water is brought down to a comfortable temperature. The wisdom of earlier generations, who sought to make the most of this celebrated spring, is still carefully carried on as a tradition today.

"Dento-yu," Entering the Bath at the Bath Master's Command

Yumomi did not come into being as an isolated custom. According to the official website of Netsu-no-yu, since the Edo period Kusatsu has had, alongside the "yumomi" that cools the water, a communal bathing method in which everyone entered and left the bath at the same time so as to disturb the very hot water as little as possible. In the Meiji era this was established as a bathing method called "dento-yu" (traditional bathing).

Its procedure is distinctive. Before bathing, yumomi is performed first; then, to prevent dizziness, more than 30 pails of hot water are poured over the head with a hand bucket. At the command of the yucho (bath master) everyone enters the water at once, for exactly three minutes. At another command they all get out together. This was repeated four times a day — a bathing method rather like ascetic training. At its peak it was practised at six bathhouses, and it is said that it was actually carried out at Netsu-no-yu until 1957. Today it is carried on at "Chiyo-no-yu."

The boards used for yumomi are about 180 centimetres long. According to the official website, yumomi is said to have not only the effect of lowering the temperature but also the effect of softening the water, and the meaning of a warm-up exercise before bathing. In other words, it was not simply a task for letting heat escape, but a whole set of manners for confronting scalding water properly.

The Yumomi Song "Choina Choina"

The song sung to keep the rhythm during yumomi is the "Kusatsu Yumomi Uta." There are three folk songs that represent Kusatsu Onsen — Kusatsu-bushi (Dokkoisho), Kusatsu Yumomi Uta (Yohohoi) and Kusatsu Kouta (Yoitosanosa) — and collectively they are called yumomi songs.

Kusatsu-bushi has been sung with all sorts of lyrics attached to it over the years, but the person who created the form we know today was Hirai Banson, who visited Kusatsu in 1918. Kusatsu Kouta, for its part, was created in 1928, with lyrics by Soma Gyofu and music by Nakayama Shinpei. When the call of "Choina choina" rings through the hall, the movement of the boards and the beat of the song line up exactly, and just watching sets your own body swaying.

The Story of Netsu-no-yu and the Flow of the Show

The yumomi show began in 1960. Netsu-no-yu itself was rebuilt as a tourist facility in 1968, and that building was enjoyed by a great many people for as long as 46 years, until 2014. Its stained-glass-style entrance, based on woodblock prints depicting dento-yu bathing, was lit from the inside at night and is said to have been popular as a photo spot. Then, in April 2015, Netsu-no-yu was reborn as a Taisho-romantic-style building. The light-filled interior has a two-storey atrium and the fragrance of wood.

The "Yumomi and Dance" show programme is in four parts.

1. Opening film 2. Dance [Kusatsu-bushi] 3. Yumomi demonstration [Kusatsu-bushi] 4. Dance and yumomi [Kusatsu Yumomi Uta]

The highlight is without question the third part, the yumomi demonstration. Performers in matching costumes slide the long boards into the water and push them powerfully back and forth in time with the song; the surface of the water ripples and steam rises all at once. The trick to watching is to queue early, in time for ticket sales, which begin 30 minutes before the performance. Seats can be chosen freely, so if you want to be right up close to the steam and the singing, the front rows have the advantage. Planning your time — for example strolling around the Yubatake and then going in to match the performance time — means no time is wasted.

Netsu-no-yu, Home of the Yumomi and Dance Show

At "Netsu-no-yu," right beside the Yubatake in the centre of Kusatsu Onsen, you can enjoy a show that recreates the traditional yumomi. The sight of women in matching costumes moving the boards in unison to the singing of Kusatsu-bushi and the yumomi songs is lively and thoroughly worth seeing. Time is also set aside for members of the audience to try yumomi for themselves, making it perfect for creating memories of your trip. It is a popular spot where you can learn about and experience Kusatsu's hot spring culture in an enjoyable way.

Kusatsu's Seasons and Annual Events

Summer features large festivals and outdoor concerts, while the winter ski season makes combined hot spring and skiing trips popular. Enjoy Kusatsu Onsen bustling through all seasons.

Best Season and Access

The yumomi show is held at "Netsu-no-yu" throughout the year, so it can be enjoyed in any season. Kusatsu Onsen itself has its own appeal in each of the four seasons — winter, when you can bathe while watching the snow, and summer, when the highlands are cool. For access, it is about 25 minutes by bus from "Naganohara-Kusatsuguchi Station" on the JR Agatsuma Line. The area around the Yubatake at the centre of the hot spring town can be explored on foot, and Netsu-no-yu is right nearby. Enjoy a trip that only Kusatsu can offer, taking in one of Japan's great hot springs and 300 years of traditional bathing culture at the same time.

Practical Information

• Facility name and address: Netsu-no-yu (414 Kusatsu, Kusatsu Town, Agatsuma District, Gunma Prefecture 377-1711)
• "Yumomi and Dance" show times (six performances a day)
• March to November: 9:30 / 10:00 / 10:30 / 15:30 / 16:00 / 16:30
• December to February: 10:00 / 10:30 / 11:00 / 15:30 / 16:00 / 16:30
• It operates every day throughout the year, but performances may be cancelled for maintenance or events
• Admission: adults 700 yen / elementary school students 350 yen (tax included). On presentation of a disability certificate, the holder and one accompanying person pay half price
• Tickets: reservations are not accepted. Only same-day tickets are sold, from the sales counter at the venue, starting 30 minutes before each performance. Payment is by cash or PayPay only (credit cards and other QR payment methods cannot be used). For popular performances it is safest to queue early
• Yumomi experience: Sundays and Mondays only, 11:30–13:00 (last entry 12:50), 300 yen for elementary school age and above (tax included). This too cannot be reserved and is cash or PayPay only. These are the only two days on which you can actually hold a yumomi board, so if the experience is your aim, plan your visit for those days
• Access: 5 minutes on foot from the Yubatake sightseeing car park / 5 minutes on foot from Kusatsu Onsen Bus Terminal / 10 minutes on foot from the Sainokawara Park car park
• Parking: Netsu-no-yu has no car park of its own. Please use the Yubatake sightseeing car park (tel. 0279-88-2704) or the Sainokawara Park car park
• Enquiries: Netsu-no-yu, tel. 0279-88-3613 (reception 8:30–17:00) / Kusatsu Onsen Tourism Association, tel. 0279-88-0800

*(Source: Kusatsu Onsen Netsu-no-yu official website)*