This vast kitty-themed collection illustrates the history of human-cat interaction.

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

Mysterious library of an infamous financier and spiritual seeker.

The world's longest known cave system.

The world's largest set of the ten commandments lay nestled in the heart of the Great Smoky Mountains.

A 131-year-old wunderkammer of Texas history.

This replica of the Greek structure is in the heart of Nashville.

Bat house that has only ever housed bat for one night; they all flew away and never came back.

An abandoned water sports stadium that has become a haven for graffiti and decay.

Enormous lake at the bottom of a unique cave system.

Labor provided by Great Depression-era programs restored these 25,000 acres in Tennessee.

One person’s lost luggage is another person’s treasure.

More than five miles of underground passageways.

Live long and prosper in Tennessee.

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

This historic train station has been converted to a locomotive themed hotel.

This abandoned NASA launch site is now a memorial to a trio of astronauts who were killed there.

A building so large that it has its own weather.

A bizarre roadside attraction and the first instance of miniature golf in the world.

The mysterious wonder of an underground waterfall is illuminated by multicolored lights.