Around half a million years ago, these magnificent columnar basalt cliffs were formed from cooling lava.

More than five miles of underground passageways.

This mysterious twin turboprop Grumman G-159 covered in graffiti has spent a decade and a half abandoned.

A 131-year-old wunderkammer of Texas history.

Two small markers remember the Alamo's feline protectors.

Legend has it the commander of the defenders drew a fateful line in the dirt with his sword just before the final battle.

This hidden sculpture garden full of Wild West art is one of San Antonio's best-kept secrets.

Conflicting markers on its floor tell a tale of two city centers in San Antonio.

A beautiful 62-acre Catholic shrine and botanical garden.

This 19th-century museum inside of a lighthouse is only accessible during low tide.

The location along the shores of the Great Salt Lake of what was once called, "The Coney Island of the West", now sits barren due to arson and time.

A 200-year-old bar is all that remains of one Mississippi River town's rough-and-tumble past.

This ancient settlement contains some of the largest earthen mounds in North America.

The remains of the dam that unleashed a 15-foot wall of water on Denver.

In a dry, neglected cemetery lies the unassuming grave of a soldier vilified in life but celebrated in death.

Oddly shaped rock formation, misassociated with a nearby utopian community.

Few things look more out of place than the electric blue ponds in the reddish-brown desert of Utah.

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

This volcano rises like a giant anthill from the plains below, with a road spiraling up to the rim.

At least seven hues of blue and turquoise make this freshwater lagoon unique.

The final resting place of American icon Buffalo Bill, and a museum that aids in telling his tale.

This small piece of railroad history sits behind the parking lot of a chain grocery store.

This Boeing KC-97 tanker is now a restaurant for aviation lovers.

This water tower slanted at an uncomfortable angle off the old Route 66 was an ingenious marketing ploy.