A megalith 4 m high and 6.6 m in circumference in the mountains of Hata Town.
It is said that, long ago, Hodo-Sennin stated: “If a good person pushes this boulder, it will move, but if a bad person tries, it will not budge.
If you push it and it does not move, it means that there is evil inside you. You must repent of your sins and return to the way of an honest, good person.”
In this way, he sought to reform bad people into good people by making them push the boulder and test their own hearts.