Funatsu Tainai Lava Tree Molds
When lava from a volcanic eruption sweeps through a forest, the shapes of some trees remain as cavities in the rock after it has cooled. These are known as “lava tree molds.” The Funatsu Tainai Lava Tree Molds preserve the shape of several trees that fell together, creating a long, round tunnel. With its “ribbed” walls formed by the cooling lava and white “milk” dripping from stalactites overhead, the tunnel was seen by Fujiko pilgrims as a passage through the body of Mt. Fuji. To crawl through it, they believed, was to be born again, and they named the tunnel Tainai, which literally means “in the womb.”
Traditionally, worshipers would purify themselves, strap special sandals to their knees, and then crawl through the tunnel. Small icons of Buddhist deities were placed inside for worship, including images of Dainichi Nyorai, the buddha traditionally associated with the mountain, and Kannon, the bodhisattva of mercy. After emerging from the tunnel, pilgrims drank a seaweed soup traditionally fed to infants. Souvenirs from the passage were prized in Edo (today’s Tokyo) and the surrounding Kanto region. Pregnant women would wear tasuki cords that had been soaked in Tainai “milk,” and burned the unused portion of candles used in the passage as a charm for safe delivery.
Today, visitors can crawl through the Funatsu Tainai just as those pilgrims once did. The lighting is now electric, and helmets are supplied for safety. Utsumuro Sengen-jinja Shrine, which was built over the lava molds, is home to several stone monuments erected by Fujiko pilgrims to proclaim their piety and achievement in scaling the peak.
Yoshida Tainai Lava Tree Molds
Less than a kilometer to the southeast is another compound tree mold called the Yoshida Tainai. Discovered in 1892, the Yoshida Tainai was immediately viewed as a sacred place by the Fujiko chapters that had survived. The entrance is visible, but visitors are only allowed to crawl through the tunnel on April 29, the day of the annual Yoshida Tainai Festival.