Kawaguchiko Field Center / Funatsu Lava Tree Molds

A lava tree mold is a hollow that is left after hot lava has covered a tree, cooled and solidified, and burned away the covered tree.
The Funatsu Lava Tree Molds are formed by a number of trees that have fallen on their sides and are connected to each other. Combined with strange patterns, they look like the interior of the human womb.