Taishoya Shiibasanso

Ureshino's valley hideaway: 20 rooms strung along a mountain stream, each with its own hinoki bath of free-flowing spring water, a huge riverside open-air bath and fireflies in June — but the big baths are recirculated, the outdoor corridors are a maze, and the food is solid rather than special

Shiibasanso was opened in April 1995 by Taishoya, a Ureshino inn founded in 1925, as a retreat in the Shiiba valley above the spa town. Its 20 rooms — mostly a 10-tatami room plus a twin bedroom — stand like stepping stones along the stream, linked by roofed open-air corridors; a travel-guide stay report credits the design to Itagaki Yaya, a disciple of the architect Junzo Yoshimura. Every room has its own bath of spring water, which the booking sites list as 100% free-flowing, and the riverside Shiiba-no-yu, added in 1998, is billed as Ureshino's largest open-air bath. Most recent evidence comes from booking-site reviews: Japanese guests rate it 4.7 across 886 reviews on one major site (baths and service 4.8), 4.52 across 556 on another and 4.65 across 76 on a third. They praise the quiet, the waterfall lit up at night, fireflies from late May, the staff's warmth (one guest with a wheelchair user called the barrier-free room the best they had found) and the melting onsen-tofu at breakfast. The complaints, dated 2025–2026: aging rooms with musty smells or weak heating, insects and humidity in summer, crowded shared baths in the school holidays, a dining room with no partitions, Saga beef too fatty for some, a breakfast buffet several repeat guests find ordinary, and a sloping site of stairs and outdoor walkways that a 2022 blogger called a maze, along with thin walls. The shared baths are heated and recirculated. Two-meal stays for two run from about ¥55,000 to ¥70,000.