A walk through the historic city center, under the streets of Seattle.

If drivers cross the rumble strip on this stretch of Route 66 at just the right speed it plays "America the Beautiful."

The second-largest cave chamber in the world was discovered in 1898 by a 16-year-old and a friend known as "Pothead."

Explore the largest pure gypsum deposit in the world, and go dune sledding while you're at it.

A haunted hot springs hotel that went from healing retreat to asylum before it was restored.

An institution that preserves the history of institutionalization.

The longest continuous lava tube in Oregon.

The second largest waterfall by volume in the U.S., Willamette Falls is outdone only by Niagara in the amount of water that is pushed northward.

The lush coastal city of Astoria is riddled with forgotten secret sidewalks.

The magic's in the hole!

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

The seamy, underground secrets of Portland's criminal past.

On the Oregon coast there is a natural hole that seems to be draining the sea.

This 19th-century Hamptons windmill was once home to modernist painter Agnes Pelton.

An old saloon in the West filled with history, and according to some, a few dozen ghosts.

'Cause the fence start shaking, the earth was quaking.

Stepping away from the glitz of mobsters and casinos to learn about the other history of Vegas.

Nevada's largest cactus collection stands outside a candy mogul's small factory.

Concentrated around the Dead Sea, these surprising canyons are filled with coursing water, fish, and even crabs.

Israel's first dedicated natural history museum is home to 5 million specimens and still growing.

Millions of years of oxidation make a drive down this winding Death Valley road surprisingly colorful.

Those with a sharp eye can find the hidden image of a German Shepherd on the memorial's Mural Wall.

The innocent intentions of this monument are somewhat lost in the sculpture's muscled imagery.

The beautiful, fruit-covered facade hints at this building's former life.