A turn-of-the-century architectural marvel built on healing mineral springs and salt licks.

Symbolic attempt to overcome the issues of life.

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

The overgrown remains of one of the premier auto-racing speedways in the Midwest—and also one of the most deadly.

A volcanic core jutting above the plain between the Snake and Boise Rivers, a marker identifies the reference point for all U.S. Government Surveys in Idaho.

One of the "twins" in these falls on the Snake River was sacrificed for hydropower generation in the 1930s.

This combination shop and museum is filled with curious items and artifacts.

A museum dedicated to the history and art of staying clean.

The mayor made the declaration in 2004.

Once adorning a New York skyscraper, these reclaimed ruins now haunt an Indiana park.

A sculpture of a flying hawk made from colorful car doors.

This fast-food outlet is the only space and UFO-themed McDonalds in the world.

This large, castle-like structure is hidden amid the mountains on the grounds of the Utah State Hospital.

Not your typical pet cemetery.

At this gas station in the middle of the desert, a convenience store has been carved directly into the rock.

These headstones and a few stone foundations are all that remain of a once-booming mining town.

Kay Andrews's recipe was so good, her family immortalized it in stone.

One of the world’s largest collections of petroglyphs records 2,000 years of human activity.

A striking, menacing sandstone peak towering above a landscape that's equal parts Mordor and the Moon.

This ghost town was once a cult-like religious utopian settlement.