The world's largest key collection features keys to the White House, Frankenstein's castle, and Hitler's bunker.

A whimsical tower with a spiral staircase, inspired by the Space Age and the Möbius strip.

Nature's biggest mammal swims in landlocked Oklahoma.

This 100-foot tall bluff located in the western plains of Kansas overlooks a massive reservoir.

Six beautiful wooden giants are hidden around Copenhagen.

The grandson of a Kiowa chief created what has become the iconic symbol of a city on the Plains.

A museum and apothecary garden devoted to the history of frontier medicine.

After a catastrophic forest fire, a Greek artist transformed scorched tree trunks outside an old sanatorium into this haunting sculpture garden.

An immersive art experience built by local arts collaborative, Factory Obscura, in the building formerly known as The Womb, a psychedelic arts center founded by the frontman of the Flaming Lips.

Travel through the hidden underbelly of the city in colorful tunnels filled with art and history exhibits.

Named for the 39 tribes that live in Oklahoma, this restaurant's menu deliciously highlights local flavors.

A home made entirely from scrapped, reclaimed and recycled material in Whitman County, Washington.

Gleaming self-built castle towers made from beer cans and inspired by "Vitamin Mary Jane."

This haunted hotel built on natural springs once served as a hospital for a quack doctor promising a cure for cancer.

The Ozarks' strangest dwelling.

An outsider art studio that created a piece of work so popular they had to turn mainstream.

This one-room schoolhouse in rural Arkansas dates to the 1920s, but looks like it could be the 1820s.

The final remnant of the Arkansas zinc industry is this historically protected ghost town.

An abandoned, rusty old relic of railroad history stands at attention over the Cuyahoga River.

This historic hotel on Bathhouse Row in Hot Springs National Park has a storied history of gangsters and baseball greats.

A beautiful South Korean gate and garden in Little Rock honors American Taekwondo.

The Man In Black grew up in a large agrarian community established by the federal government in the Great Depression.

A restored schoolhouse was once a vital part of the Black mill workers community in Arkansas.

Walk through row upon row of manicured miniature trees at the United States' largest bonsai nursery.