These are one of Japan’s natural wonders. They are created by the changing tides in the Naruto Strait between Shikoku and Awaji Island and are an absolute must-see. The whirlpools occur approximately every six hours and last for an hour or two, varying in size and intensity depending on the tides.
There are various options to see them. The best view can be had from the tourist boat that sails right next to them. Another option is from Uzu-no-Michi, the observatory walkway built right underneath the Onaruto Bridge, offering spectacular views 45m above the whirlpools through glass panels set in the floor.