The "World's Largest Underground Business Complex," a 55,000,000-square-foot city underneath Missouri.

The world's largest man-made underground caverns offer unparalleled underwater wonders.

The history of the treatment of mental illness, illustrated in all its gory detail, and housed in an asylum.

European castle ruins in an American state park are actually the product of death and grief.

Famous church recognized for both its unique design and disciplined monks that live according to the Benedictine discipline.

This rare, carefully curated collection showcases the history of neon inside a grandiose Elks lodge.

This old-fashioned roadhouse's quirky neon sign is as famous as its enormous dumplings.

Inside a humble hangar is some of the best roller derby the world has to offer.

The world's last remaining store of its kind.

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

Portlandia is the second-largest copper repoussé statue in the United States.

Instead of fruit, the branches of this tree are brimming with hopes and dreams.

A sculpture of a salmon swimming through a brick building.

This stoic, if derpy, giant stands as a monument to Oregon's statehood and the novelty culture of yesteryear.

Despite a legend that says this highest peak in Oregon was climbed in high heels scores of people have died on its slopes.

This abandoned boat sits on a nude beach, is shaped like a UFO, and is covered in graffiti.

A delightfully quirky blend of oddities spread throughout an old 1920s bank.

10,000 flowered plants bloom in the City of Roses.

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

A massive sea stack famous for its appearance in The Goonies.

Only known mainland rookery of the threatened Stellar sea lion.

The longest continuous lava tube in Oregon.

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

The eerie remnants of an ancient forest were hidden under the sand for centuries.