Often referred to as the largest spring in America.

One of the deepest springs in Missouri.

The lobby of this hotel near the U.S.-Mexico border features a stained-glass mural that measures 42 feet long and 6 feet tall.

An abandoned munitions storage facility with a rich architectural history.

A historic, scenic mill that was forced to close due to overlogging.

This former mining railroad is one of the best-preserved short lines in North America.

An average of 33 million gallons of water pour out of the collapsed cave at the heart of this spherical spring.

An art gallery home to a plethora of art from local artists who can often be seen hard at work.

Despite the name, it's unclear if this small depression in northern Nye County was actually caused by falling space debris.

Irontown was founded in 1868, as a second attempt to mine iron from the nearby Iron Mountain.

Dedicated to a U.S. Army lieutenant colonel who was also a bird watcher and artist.

Hidden behind an empty field resides this early 19th-century cemetery.

These unique rock formations were created during the Ice Age.

This Colorado fire station has been in continuous operation for more than a century.

Unruly residents were housed in this one-person cell until the Black Maria arrived.

A Jurassic artscape composed of transmission casings and other mechanical parts.

This cemetery is one of the last remaining traces of a drowned old Western town.

Once the smallest park in the national system.

Narrow gorges and deep pools created by long-ago glaciers.

No passport is required to eat around the world at this elegant restaurant.

A bookstore with an entire room dedicated to damaged and forlorn comic books.

It’s all about the Benjamins at this Atlanta museum with interactive exhibits.

The home of a 19th-century author who brought African-American folktales to the mainstream is now Atlanta’s oldest house museum.

On land once deemed “valueless,” a multipurpose community garden proves the potential of urban farming.