A pair of giant roadside arrows are all that remains of a former Route 66 trading post.

The massive, incredibly rare instrument is over 11 feet tall with a range so deep it goes lower than humans can hear.

The final resting place of the businessman-turned-astronomer who helped discover Pluto stands near his observatory.

Ninety feet off the valley floor is an ancient dwelling put under protection of the U.S. government by Teddy Roosevelt.

A Wild West jailhouse that slid down the mountainside.

This centuries-old graveyard is the final resting place of the Fort Fisher Hermit.

A miraculous natural phenomenon known as "the spring that breathes."

A mysterious monument meant to be a guide into "an Age of Reason" was destroyed after an apparent bombing.