A mailbox that saved a nature reserve.

This nine-story building can be played like an instrument.

This research center for rare prosimians is studying how they sleep to help prolong human life.

One of the best places to see feral Colonial Spanish Mustangs in the United States.

Gnarled canopies of pink and purple wildflowers arch over the trail to the summit.

Garden dedicated to native carnivorous plants and site of huge flytrap heist.

A historic covered bridge, only one of two remaining in North Carolina.

The highest point in Tennessee, Clingmans Dome bears witness to the ravages of one type of insect.

This road in the Great Smoky Mountains was supposed to assuage a displaced community, but ended up a $52 million dead end.

A sculptor's dream castle turned fantastical ruin.

A former Oz-themed attraction that has fallen into disrepair, but still holds some of the original magic.

Mysterious ancient boulder carved with petroglyphs in the mountains of Western North Carolina.

This woodland architectural installation acts as a camera obscura for the heavens.

This structure among the trees was the result of divine inspiration.

This mansion turned restaurant was once a pitstop for Al Capone during his travels.

Ethereal alien hums and haunting whale songs emitting from...a giant sheet of vibrating metal?

This large cave is a summer home to thousands of bats and has a rich history dating back to prehistoric times.

Abandoned for 60 years, this submerged bridge was completely forgotten until the lake was drained.

Hiding behind a grocery store is a spectacular cavern carved as part of an old limestone quarry.

Mysterious library of an infamous financier and spiritual seeker.

The "Jade Museum" is full of thousands of intricately carved works of art made from various precious stones.

The site of the one of the most deadly train wrecks in American history.

Once decrepit and slated for demolition, now one of the longest pedestrian bridges in the world.

An engraved boulder marks the spot where Patsy Cline's life ended in a plane crash.