Isawa Onsen — Fruit Valley Hot Springs

Isawa Onsen, located in the Fuefuki Valley surrounded by peach and grape orchards, is Yamanashi's largest hot spring resort with over 50 ryokan drawing from alkaline mineral springs discovered in the 1960s. The onsen water is clear and slightly slippery (due to alkalinity), with reputed benefits for skin smoothness — leading to its nickname 'bijin no yu' (beauty hot spring). The area combines onsen bathing with Yamanashi's famous fruit agriculture — many ryokan offer seasonal kaiseki meals featuring local peaches, grapes, and wine.

The distinctive feature of Isawa Onsen is its free public foot baths scattered throughout the resort town — over a dozen ashiyu (足湯) where visitors can soak their feet while exploring the streets. The largest is Fuefuki-gawa Fruits Park's 40-meter foot bath, located alongside the Fuefuki River with views of the surrounding mountains. The resort atmosphere is relaxed and family-oriented, catering primarily to domestic tourists seeking a quieter alternative to Hakone or Atami.