Once a year, on June 26th, you can bathe outdoor hot spring bath at any of the 24 ryokan belonging to the Kurokawaonsen Ryokan Association for free!
Schedule is as follow:
date: June 26th
time: 10:00 am ~ 3:00 pm
Don’t forget to pop into the reception of the ryokan first before heading off to use the baths!