A miniature rainforest is growing inside of a Midtown Manhattan office building.

A treasure trove of artifacts, books, and artwork from the "golden age" of exploration.

La Monte Young and Marian Zazeela's "Dream House" will immerse you in an ever changing world of sound and light.

A volcanic fissure over two miles long and up to 70 feet deep.

A volcanic landmark located on an Ice age lake bed.

The deepest lake in the United States, and once the site of epic destruction that lives on in legends.

A chance to sleep among the firs and pines of the Oregon forest.

Treehouse motel and treehouse-building school.

A botanic garden full of trees twisted into fantastic shapes and positions.

Each winter this underground cave forms a dazzling ice palace.

Trails through lava-carved tube-caves display sparkling bacteria and a rich history.

An abandoned cyanide mill is now a haunting magnet for graffiti and illegal parties.

Eastern zen meets Western grit in these four little trees growing out of a rock on Lake Tahoe’s Nevada shore.

The now-abandoned tunnels were built for the transcontinental railroad on the route where the first wagon train entered California.

This diner's a kitschy dreamland for anyone whose heart is stuck in the 1980s.

Each summer, the migratory bats living beneath the bypass form "batnadoes" at dusk.

This museum boasts the ninth-largest collection of insects in North America.

This graffiti-covered bridge is the quintessential vision of a place for disillusioned youth to escape the complexities of burgeoning adulthood.

The largest drain hole in the world.

California's own majestic geyser is powered by a subterranean volcano.

The fossilized remains of ancient California redwoods.

Nursery with extensive collection of flesh-eating plants operated by the author of "The Savage Garden."

The haunting ruins of Jack London's dream house.

The unedited photograph called "Bliss" has graced the screens of over a billion computers.