Sandstone rock formations that look like they belong on the cover of a progressive rock album.

A popular swimming hole that hides one of America's most deadly diving spots.

An outdoor sculpture park of giant pink robots and post-apocalyptic Christmas scenes.

Brightly colored 30-foot-tall totems light up the desert sky just outside Las Vegas.

An arsenic-filled pool in the Grand Canyon takes on the appearance of a giant, overflowing pumpkin.

Historic funicular railway, believed to be the shortest railroad in the world.

An extraordinary mixture of natural beauty and man-made phenomena.

This lake in the Cascades lives up to its name, disappearing down a hole every spring.

This Big Sur waterfall drops 80 feet directly into the Pacific Ocean, and inspired the hillside house up top.

This rugged area of red rocks and arches is often considered one of the most beautiful places on Earth.

Less a museum than a bizarre fantasy world created by artists and engineers.

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

Hidden beneath a bridge, this waterfall is known for the large amounts of graffiti painted on its base.

This charmingly homemade amusement park has been growing for 40 years.

Canyon walls shrouded in ferns.

This "zoo" is a cross between a junkyard and a sculpture garden, featuring animals you won't see anywhere else.

An abandoned castle owned and ignored by Masons carries a cursed history.

The oldest surviving bridge in New York City, which reopened to pedestrians in 2015.

A mysterious castle built as a monument to lost love.

A historic neighborhood church is reborn as a psychedelic arts collective.

Breathtakingly blue walls shimmer inside the "Glacier Behind the Town."

Carved by a waterfall in a hard-to-reach rock formation, this heart-shaped rock has inspired romantics for decades.

In the middle of an extremely unforgiving and desolate high desert is the most secret military facility in the world.

A reproduction of earth's many biomes.