Mysterious rocks that ring musically when struck.

A midcentury ranch house hides a literal treasure trove of unique rocks and minerals.

Western Europe's only representation of a Roman goddess still in its original location sits in an unassuming park.

Hundreds of glow-in-the-dark objects light up a museum in a historic zinc mine.

The only remaining piece of hull of the most decorated US ship of WWII is this giant name plate.

A granite monument honors a beloved World War II canine mascot.

A Swiss board game museum housed inside a picture-perfect castle.

This 19th century train workshop is a treasure trove of railroad history.

This forgotten boat elevator was an engineering marvel in its heyday.

Knoxville’s architectural icon was the symbol of the 1982 World’s Fair, even catching the googly eye of Bart Simpson.

A sacred site for Native Americans surveyed by George Washington and owned by both King George III and Thomas Jefferson.

This collection of over 50 classic pinball machines awaits visitors to downtown Roanoke.

An unknown Hall of Fame in Jackson, Tennessee.

This Memphis recording studio launched the careers of Jerry Lee Lewis, Johnny Cash, and Elvis Presley.

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

Home to drunken tower-climbing goats... seriously.

More than five miles of underground passageways.

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

This funicular railway rumbles along for a mile up the nearly vertical face of Chattanooga’s Lookout Mountain.

Hidden beneath the streets of London is a secret subway that only carried mail.

Sunset-colored dunes of volcanic ash make taking a poor photo impossible.

Once in disrepair, this popular Texas stop along iconic Route 66 has been restored to its past glory.

The site of the little-known Pennsylvania battle that sparked the Seven Years' War.

These remote Florida islands have a history of sea turtles and sunken treasures, and one of the world's largest coastal brick fortresses.