Hyotan'ike Pond Park is situated on the top of a hummocky hill, which was created by the collapse of Mt. Mayuyama. This hummocky hill is one of the largest of its kind, and its undulating surface was used to make a pond. The pond has been later developed into the Hyotan'ike Pond Park. From here, you can observe the huge mountain wall that was formed when Mt. Mayuyama collapsed.