K's House Ito Onsen

This is a real hot-spring bath inside a budget hostel: water piped straight from the source and kept flowing rather than recirculated, split between one large shared indoor bath and two private baths that guests can reserve for free. Guests often mention having the private bath to themselves and call it the best part of staying here. The building carries the real story: a roughly century-old former ryokan, now a nationally designated tangible cultural property, that K's House converted into a hostel in 2010. Wooden floors creak underfoot, and river-facing rooms look over the water running through Ito, with bamboo lanterns lit along the bank at night. It draws a quiet mix of Japanese and foreign travelers here for a good soak and a cheap bed rather than anything flashy.