Yamamizuki

Riverside open-air baths and some of Kurokawa's warmest service, a shuttle ride from the village — excellent value, if you book a room with its own bath

Yamamizuki is a 21-room inn beside a mountain stream about 2 km outside the centre of Kurokawa Onsen, and Japanese guests rate it very highly: 4.64 out of 5 across 484 reviews on one major booking site, 4.8 across 578 on another (baths 4.9) and 4.5 on a specialist onsen site, where service scores a perfect 5.0. The draw is bathing next to running water. The inn calls the men's open-air bath, Yūkoku-no-yu, its symbol, where you hear the river and watch the trees move; women have their own open-air bath, Mori-no-yu, reached by a path through riverside woods. Bloggers describe hot water — around 45°C outdoors — thick with mineral flakes, and a spring the inn calls gentle on the skin. The service is what turns guests into fans: in 2022 luggage went ahead to the inn while guests were dropped in the village to explore, in 2026 reviewers still describe being met in the car park and waved off at checkout, staff greet guests even outside the property, and one blogger with decades of onsen trips called it their favourite. Two 2022 bloggers paid about ¥40,000 for two with dinner and breakfast and wondered how the inn could charge so little; 2026 reviewers report roughly ¥42,000–60,000 or more for two. Criticism is mild but consistent: meals can arrive slowly, dinner has occasionally been served cooler than it should be, two guests (the latest in September 2026) found stains on the tatami, a 2026 guest heard neighbours through thin walls, and older reviews found the cooking refined rather than hearty.