The Ogre’s Washboard, 鬼の洗濯板, interesting rock formations on the way to Aoshima Shrine. The Ogre’s Washboard is a geological formation of an accumulation of sediment that occurred a few million years ago deep under the ocean. This formation has been shaped from the erosion of waves and now protrudes out of the sea at a slight slope The result has been the creation of nature when this formation is not underwater, making this area a unique landscape not seen anywhere else. (description from http://www.welcomekyushu.com/event/?mode=detail&isSpot=1&id=9999900000001)