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

Most-visited and most-photographed slot canyon in the American Southwest.

Tucked away in the forests of Indiana resides an abandoned waterslide that is now a popular graffiti haunt.

This former tuberculosis research hospital endeavored to cure the dreaded disease with fresh air and positive attitudes.

A stretch of highway even lonelier than the so-called "Loneliest Road in America."

This bridge was constructed from the remains of the first Ferris wheel.

Walk in the footsteps of the famed astronaut at Purdue University.

Tombstones carved to look like tree trunks are used for multiple generations of family members.

A small rural town hides Indiana's tallest waterfall.

One of Indiana's only natural sandstone arches is nestled between resort ruins and an old Boy Scouts camp.

The first spinning jail built in the United States is the only one that still turns.

A hidden network of subterranean passageways lies tangled beneath Indianapolis' bustling City Market.

For over 100 years, this Indiana town has had a tree growing out the top of the local courthouse.

This former office building has been transformed into an immersive music venue and art space.

A curiosity-seeker's paradise set inside a three-story historic school house.

Inspired by a piece of concrete, these three pyramid-shaped buildings have been beloved Indianapolis landmarks for over 50 years.

The world's longest known cave system.

Once one of the most polluted caves in America, now an environmental success story and a museum dedicated to caves.

An abandoned theme park with a strange and tumultuous past.

One of the few surviving "Wigwam"-themed motels.

When local government began removing public benches, the public pushed back, and vibrant, community-built seating now outnumbers the official shelters at Chattanooga bus stops.

Software company Epic Systems has created one of the strangest and largest workplaces of all time.

More than 5,000 contemporary and "historic" mustards from around the world.

The only thing these street signs will help you navigate is your imagination.