First-Time Gunma: Kusatsu's Hot-Water Field & the Tsumagoi Highlands — 2 Days

The Yubatake, the 'hot-water field', is the heart of Kusatsu and one of the iconic images of onsen Japan: a sloping bed of long wooden channels in the very centre of town through which the spring water runs to cool from its scalding source temperature before it is piped to the baths, throwing up a constant cloud of sulphurous steam. Pale yellow sulphur deposits, the yu-no-hana harvested from the channels, line the wood. A stone promenade rings the field, and the surrounding lanes of inns, bathhouses and sweet-shops radiate out from it. It is the natural place to begin: Kusatsu has poured out hot water here for many centuries, and the Yubatake is the visible engine of the whole town.

Open and free at all hours; the field is illuminated after dark and is at its most photogenic in the early evening. In the centre of town, a 5-minute walk from the main bus terminal. Allow about 45 minutes, more in the evening. The water and steam are strongly acidic and sulphurous.

Kusatsu's spring water emerges far too hot to enter — close to 50 degrees — and rather than dilute it with cold water, which would weaken its famous properties, the town developed yumomi: cooling the bath by stirring it with long wooden paddles. At Netsu-no-Yu, a handsome bathhouse-style hall facing the Yubatake, performers in indigo work the long boards through the steaming water in time to traditional Kusatsu-bushi work songs, and visitors can try a turn at the paddles. It is part folk performance, part living demonstration of how a town learned to live with water hotter than it could bathe in.

Yumomi shows run several times daily, roughly between 09:30 and 15:30 (reconfirm the day's schedule on arrival); around ¥800 adult, ¥400 child (approx., 2026). Directly facing the Yubatake. Allow about 45 minutes including the show.

A long-running soba house a step from the Yubatake, Mikuniya is the easy, honest lunch between a morning at the hot-water field and an afternoon in the baths. Buckwheat suits the cool highland climate of Kusatsu, and the kitchen serves it both cold with dipping sauce and hot in broth, with tempura of the season alongside. It is unpretentious and quick, exactly what you want before a long soak: order, eat well, and be back on the lanes within the hour.

Open for lunch, typically from around 10:30; closed Tuesdays (approx., 2026 — reconfirm). A soba set runs roughly ¥1,000–1,800 (approx., 2026). On the Yubatake-front street, about 125 m from the field. Allow about an hour.

At the western edge of town, the Sainokawara is a riverside park where hot spring water seeps and steams out of the very ground, and at its far end lies one of the largest open-air baths in Japan: a broad stone pool, ringed by trees and rock, where you bathe in Kusatsu's pale, acidic water under open sky. The walk up through the steaming park, past little rills of hot water and pools too hot to touch, is half the pleasure. Separate baths for men and women; bring a towel or rent one at the entrance.

Open daily, roughly 07:00–20:00 April–November and 09:00–20:00 December–March; admission around ¥700 adult (approx., 2026 — figures vary, reconfirm at the gate). A 10–15 minute walk west from the Yubatake through Sainokawara Park. Allow about 90 minutes with the walk and a soak.

Hotel Ichii faces the Yubatake directly across the promenade and is one of the town's long-established inns, renovated in 2024. Its baths draw on Kusatsu's own springs, and a Yubatake-view room puts the steaming, floodlit field below your window after dark. As the recommended base for the night, it places you a few steps from the show, the soba and the evening illumination, with a proper kaiseki dinner and the town's renowned water on tap. Check in, soak, and head out to see the Yubatake glow.

Yubatake-front; renovated 2024 and taking 2026 bookings. Rates vary by season and room; a Yubatake-view room with two meals is the splurge. Right on the central promenade. Listed here as the night's sleep anchor; an alternative heritage choice is the ryokan Naraya nearby. Allow about an hour to check in and bathe before dinner.

For a relaxed dinner off the inn's set menu, Mizuho is a small izakaya beside the Yubatake serving hand-cut udon, grilled skewers and local dishes alongside Gunma sake and shochu. After dark the field is lit and the lanes quiet down, and a bowl of hot udon with a drink is the right end to a day of bathing in the highlands. It is a few steps from the inn, so you can wander out, eat well, and be back by the floodlit water within the hour.

Open for lunch and dinner, roughly 11:00–15:00 and 17:30–22:00; closed Thursdays (approx., 2026 — reconfirm). Dishes are ¥500–1,500 each (approx., 2026). Beside the Yubatake. Allow about 90 minutes.

When Mount Asama erupted violently in 1783 — the Tenmei eruption, one of the great disasters of Edo Japan — it threw out a vast field of jagged black lava that froze into the strange, broken landscape now called Onioshidashi, the 'demon's expulsion'. Walking paths thread between the contorted rocks, and at the centre stands the Asama-yama Kannon hall, a branch of Tokyo's Kanei-ji founded in 1958 to console the souls of those killed in the eruption. The contrast of pilgrim hall and lava waste, with Asama smoking gently above, is unlike anywhere else in the region.

Open daily, roughly 08:00–17:00 (last entry 16:30); admission around ¥700 adult, ¥500 child (approx., 2026); operated by Prince Hotels. About 750 free parking spaces. In Tsumagoi-mura, reached by car or sightseeing bus from Kusatsu in about 30–40 minutes. Allow about 75 minutes for the lava paths and hall.

High on the Tsumagoi Panorama Line at around 1,200 metres, Aizuma-no-Oka — 'beloved wife hill' — is a free roadside deck overlooking the green sweep of Tsumagoi's summer cabbage fields, with Mount Asama beyond. Tsumagoi grows much of Japan's highland cabbage, and the hill became locally famous as the place where farmers shout their love for their wives across the fields, an affectionate village ritual that gave the deck its name. It is a quick, joyful stop: stand on the platform, take in the patchwork of cabbage and mountain, and drive on.

Free, open-air roadside stop with a small free car park; best in the green season. The Panorama Line (north route) closes in winter, roughly December–March; the cabbage fields are greenest July–August. In Tsumagoi-mura, about 25 minutes by car from Onioshidashi. Allow about 30 minutes.

A characterful country kappo in central Tsumagoi run by descendants of Nakaiya Shigenobu, a late-Edo merchant figure, Nakaiya serves hand-cut soba and tempura of mountain vegetables the owner forages himself. It is a substantial, regional lunch — the kind of unhurried country meal that suits a highland drive — served in a traditional house a few minutes from Manza-Kazawaguchi Station. After the lava field and the panorama, it is the right place to sit down properly before the run down to the dam.

Open roughly 11:00–20:00; closed Tuesdays (approx., 2026 — reconfirm). Cash only; parking and alcohol available. In Mihara, Tsumagoi-mura, a 5-minute walk from Manza-Kazawaguchi Station; about 25 minutes by car from Aizuma-no-Oka. Allow about 75 minutes.

Completed in 2020 after a long and politically fraught construction history, the 116-metre Yamba Dam holds back the bright Yanba-Agatsuma Lake in the valley of Naganohara. The dam itself can be visited — you can walk the crest and, on some days, descend to its base — and the adjacent roadside station, Yamba Furusato-kan, has a farmers' market, a dam-curry eatery and a footbath. On the water, the guided operator Paddle-ya runs canoe and kayak tours in season. It makes a scenic last stop before the road carries on toward Karuizawa or back to the expressway.

Dam and Yamba Furusato-kan roadside station open year-round; canoe tours with Paddle-ya are seasonal (from April), roughly ¥7,700–9,200 per adult (approx., 2026) — private craft are not permitted on the lake. In Naganohara-machi, about 35–40 minutes by car from Tsumagoi. Allow about an hour.