Yoshida Lava Tree Molds

Yoshida Lava Tree Molds consist of over sixty cave-like hollow structures formed underground when lava from Mount Fuji surrounded trees and created vertical tubes in rock. These tubes measure up to 5 meters (16 feet) deep and preserve the precise shapes of trees that lived before the volcanic eruption.

These hollow structures formed during a lava flow approximately 1200 years ago, when trees encased in molten rock created gases that protected their surfaces from erosion. During the Edo period, followers of Fujiko tradition converted them into sacred spaces for spiritual practice and contemplation.

The site hosts the Yoshida Tainai Festival each April 29th, where visitors observe traditional ceremonies and fire rituals that link people to Mount Fuji's spiritual significance.

The site is easily reached by bus from Fujisan Station to the Kankyo Kagaku Kenkyusho Iriguchi stop, then a five-minute walk to the entrance. Wear sturdy footwear since the pathways between the hollow structures are rooted and rocky underfoot.

Each hollow tube preserves the exact size distribution and internal structure of individual trees, allowing researchers to reconstruct the age and species of ancient forests. This data helps scientists understand the environment that existed before the volcanic eruption.