A sprawling cave network created by a lone lava tube.

This great stone guardian of the forest is a relic from the land's volatile volcanic past.

This gorgeous beach hides behind two headlands in Oregon's Ecola State Park.

Only known mainland rookery of the threatened Stellar sea lion.

Not-so-fearsome tiny trolls live under this wooden train trestle in Portland.

A toxic ghost town sitting atop a massive coal fire.

The remains of a community that was forced to move for a dam that never materialized still rot in this Pennsylvania park.

The only geyser in the state of Pennsylvania is caused by pressure from an abandoned coal mine outside of the ghost town Centralia.

Twenty-eight years after this local landmark was washed ashore by hurricane Hugo, it was washed away by hurricane Irma.

The language and heritage of a nearly forgotten culture can still be explored in this Southern enclave.

Paths are maintained, but trees have taken over plots.