This freshwater spring fills with 10,000 gallons of water per minute.

Strange physical sensations and optical contradictions keep visitors coming back for more.

Island where motor vehicles are banned -- home to the only carless highway in the United States.

This shallow cave got its name from copious amount of human bones found inside.

The fifth-longest suspension bridge the world, connecting one Michigan peninsula to another.

The famous Beatle secretly visited this Illinois town several times to visit his sister.

The carved remains of a 200-year-old oak tree memorialize the namesake of the iconic "Wizard of Oz" character.

Evidence from a brutal 1880s murder is on display at this former infirmary house.

This restaurant proudly displays bread signed by the 39th president.

The oldest house in Galena, Illinois, now is a reminder of when this city was the world's lead mining capital.

A sweet tribute to Georgia's official state vegetable, which even has its own mascot: "Yumion."

One of England's most famous churches hides a pair of little known architectural treasures.

One of the few standing Roman lighthouses and a labyrinth of tunnels are a couple of the secrets at this historic castle.

This private residence was the template for one of the most beloved television homes of all time.

A museum in Mississippi celebrates the history of Coca-Cola and the man who brought it to the masses.

Hollywood's most famous landmark, the "temporary" sign that has stood for decades longer than intended.

A nostalgic bibliographic gem.

The remains of a historic ranch house that witnessed the Civil War battle dubbed the “Gettysburg of the West.”

One of the most enjoyable bits of history at Coney Island and “the most romantic ride in the world.”

Ride the subways of yesteryear.

Overlooked by many, the two famous Scottish warriors guard the main gate of Edinburgh Castle.

The final resting place of soldiers' loyal canine companions.

Ruined 11th century abbey built by King David I in Edinburgh, Scotland.

Famously misunderstood wonder of the ancient world