Yubatake is the hot water field at the center of Kusatsu Onsen in Gunma, and the landmark the town is arranged around. Spring water comes up here at about 4,000 liters a minute and runs down a series of wooden channels, where it cools before going on to the town's bathhouses and ryokan. Steam rises over the channels, and the smell of sulfur reaches you before the field does. A tile-paved walkway and benches circle it, with footbaths and shops close by. After dark the area is lit, and the steam shows well in the lights.
How the hot water field works
Yubatake means "hot water field". It is a series of seven wooden channels built in the middle of Kusatsu Onsen. Around 4,000 liters of spring water well up here every minute, at roughly 55°C. The water runs over the channels and cools naturally, and the channels also collect the sulfur deposits it carries. It is then sent on to the town's hot spring facilities, which is how the ryokan and public baths get their water.
The water is strongly acidic, with a pH between 1.7 and 2.1. An iron nail left in it is said to rust away in about nine days. The long-established yumomi method of cooling the water is what makes it comfortable to bathe in.
Yumomi at Netsunoyu
Right next to the field, Netsunoyu stages yumomi, a traditional ritual in which the hot spring water is stirred and cooled with long wooden planks. The demonstrations are accompanied by folk songs and are held regularly. They show in practice what the channels do on a larger scale.
Around the field
A tile-paved walkway and benches run around Yubatake, and footbaths sit close to it. Several cafes and sweet shops are a short walk away, and some have their own footbaths.
Onsen Street leads from Yubatake to the Kusatsu Hotel. Along it are clothing and souvenir shops, stores selling tableware and glassware, and vendors with cakes, boiled eggs and other snacks. Local dishes to look for in town are kamameshi, rice cooked in a small iron pot, and Kusatsu egg pudding.
Goza-no-Yu, nearby, rents yukata. Women can choose from more than 600 combinations of robe and obi, and men's yukata are also available. Sainokawara Park, with its steaming streams and a large open-air bath, lies beyond the center. The Ura-Kusatsu Jizo spot is about five minutes on foot from the field.
A landmark the town was built around
In 1973 the town mayor asked the artist Taro Okamoto to turn Yubatake, by then heavily trafficked, into a place for recreation and relaxation. The surrounding park and promenade date from that effort.
The field sits at the center of a small town, and many of the town's directional signs refer to it. Most sights and ryokan in the center can be reached on foot. Mount Shirane, the source of the volcanic water, is about a 30 minute drive above the town.
Seasons, evenings and crowds
The field is open at all hours and is lit after dark. The steam is most visible on cool evenings and in rain, so winter nights are a good time to see it. In winter a Christmas tree stands beside it.
Daytime is livelier, with the shops and the yumomi demonstrations. Peak periods draw crowds, and weekends are the busiest. Parking is limited, so arriving by public transport saves time. Staying overnight lets you see the field in both daylight and lamplight and use the town's baths.
Preguntas frecuentes
What is Yubatake?
Yubatake means "hot water field". It is the spring source at the center of Kusatsu Onsen, where hot water runs down wooden channels to cool before it is sent to the town's baths and ryokan.
Why does Yubatake smell?
The spring water carries sulfur, and the scent is noticeable around the field. The channels also collect the sulfur deposits.
Can you see Yubatake at night?
Yes. The field is open 24 hours and is lit after dark, when the steam stands out in the lighting.
Where can you see the yumomi demonstration?
At Netsunoyu, right next to Yubatake. Performers stir and cool the hot spring water with long wooden planks, accompanied by folk songs.
Is parking easy near Yubatake?
Parking is limited and the wait for a space can be long. The town center is small, and most sights and ryokan in it are within walking distance.
