Dont miss one of japans best whitewater rafting experiences with more than 75 miles 12 km of class iii to iv rapids this half day rafting tour in minakami is a continuous roller coaster of whitewater action plus the scenic canyon sections of momiji canyon minakami canyon and suwa canyon its most active in the spring the summer tour is a mellower experience with less challenging rapids but still plenty of fun both in and out of the boat