A one-of-a-kind collection of a unique medium.

For two weeks every June, fireflies in the Smoky Mountains perform an astonishing light show.

Only museum dedicated to women pilots, with personal artifacts from Amelia Earhart and other aviatrixes.

A clear blue swimming hole with hidden caves, still unexplored.

One of the dwarven trees dates back to 1625 and survived the Hiroshima bombing.

Twin Peaks' real life Double R Diner has been restored to its damn fine television look.

Giant, natural amphitheaters made of delicate geological formations called "hoodoos."

This weird abode has inspired everything from the "House On Haunted Hil" to a robot hunter's pad.

A strange house built only at night, with rumored mystic inspiration.

An emerald-green grotto just a short trip from Austin.

Ruins of the elaborate house where the enigmatic costume designer threw glamorous parties for New York's theatrical elite.

A Muppet museum in small-town Mississippi honors the roots of Jim Henson's most beloved creation.

The highest point in Oklahoma used to be a lawless outlaw's paradise.

A half-mile long and three stories high, this bridge over the Des Moines River Valley mimics a descent into a mine shaft.

The scuba diving training facility was named for the steam that rises from the cave's chimney.

This naturally-sourced hot spring is now home to a clothing-optional resort.

This Little Rock legend has survived decades of rowdy crowds, three fires, and a zombie wedding.

The ghostly remains of what was once the world's richest copper mine.

The king of U.S. high points towers over every other peak on the continent.

This architectural triumph is the only Frank Lloyd Wright house in Alabama.

This pseudo-steampunk weapons facility is the world's largest wood and glue structure, and packs quite a wallop.

On the outskirts of a reborn ghost town, a decaying post office remembers the bad old days.

This secluded aqua waterfall in the Grand Canyon is the perfect swimming hole, and the Havasupai tribe's fiercely protected natural wonder.

Natural sonic phenomenon comes with a grisly legend of murder and blood.