• title Oni no Sentakuita Rocks
    one word explanation horizontal outcrop with visible bends
    keywords geologylegendhistory
    confirm, register Oga Quasi-National Park, The Top 100 Sites of Geological Structures in Japan, One hundred strange stones from Japan, One hundred beachies in Japan
    conservation laws and ordinances Natural Parks Act

    The beautiful Unosaki Beach has been designated as one of Japan’s Hundred Best Beaches. Because the coast is so shallow, you can see the winding shape of the sea floor when the tide is out. The shape we see today was formed 10 million years ago when the geological stratum on the sea floor rose out of the water and the softer layer was worn away by the waves, leaving only a hard layer behind. Because of this, you can find fossilized fish bones and scales here. The shape of the sea floor gives the beach its nickname, Oni no Sentakuita Rocks.

  • title Azuki-iwa (Azuki Beans) Rocks
    one word explanation round rocks found only during low tide
    keywords geologynaturebeautiful
    confirm, register Oga Quasi-National Park, One hundred strange stones from Japan
    conservation laws and ordinances Natural Parks Act

    Unosaki Beach is dotted with spherical rocks known as Azuki Bean Rocks. Because of their pretty shape, they are also called Oboko Rocks (oboko meaning “small child”). Formed from a mixture of mud and minerals such as calcium and magnesium, these hard rocks are not very noticeable during high tide, when only the tops of their heads are visible, but they can be seen in full during the early spring tide.