Pyramid-shaped Mt. Oyama is also called "Amefuri-yama" or mountain of abundant rain since it was often shrouded in clouds. Farmers prayed to the mountain for rain.

The mountain's deity, Oyama-tsumi-no-Kami, is the father of the goddess of nearby Mt. Fuji. It is also a Japan Heritage site. A great time to visit would be in mid-November for the autumn leaves.