S P O T ／ SPOT-100

Funatsu Tainai Jukei (Womb-Cave Lava Tree Mold)

船津胎内樹型ふなつたいないじゅけい

When lava from one of Mount Fuji's eruptions engulfed a living tree, the wood eventually burned away and left behind a long, sinuous cavity in the cooled stone — a tree-shaped tunnel in the lava itself. At Funatsu, this kind of cavity was reinterpreted by Fujikō pilgrims as a 'tainai' (womb), and entering and exiting through the narrow opening became a ritual of symbolic rebirth, performed by pilgrims on the day before climbing Mount Fuji to purify the body and start the ascent anew. The interior walls are striated with rib-like patterns formed where bark once stood; the local pilgrims interpreted these as the literal ribcage of the mother goddess Sengen Daibosatsu, completing the womb metaphor with anatomical specificity. The cave is a designated Natural Monument, administered today by Fujikawaguchiko Town; admission is modest, the cave is electrically lit but very narrow, and the experience of squeezing through the constriction and emerging into open air is one of the most unforgettable small rituals available on the Fuji circuit.