Eighty million natural history specimens call this gargantuan museum home.

The world's longest known cave system.

The second-largest cave chamber in the world was discovered in 1898 by a 16-year-old and a friend known as "Pothead."

The L.A. Zoo has a secret garden of rare bootleg cycads, a palm specimen dating back 280 million years.

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

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

Fascinating town where normal life interfaces with the occult.

A 1,215-foot tunnel transports pedestrians beneath the River Thames.

A showcase of canine neckwear spanning five centuries of doggie fashion and function.

Mysteriously stacked storefront paths give this medieval British town an iconic style like none other.

Controversial tribute to the heavyweight champion boxer who grew up in Detroit.

The 80-foot tire that looms over Michigan's I-94 was once a Ferris wheel in the New York World Fair.

Weighing 30,000 pounds, this monument represents Detroit's first industrial era.

The Beaux-Arts aquarium boasts a vast collection of saltwater and freshwater fish on an island in the Detroit River.

A Beaux-Arts triumph set to become Ford's innovation campus

Concrete igloos standing across from what remains of the Michigan Central train depot.

Hell on Earth is actually a small town in Michigan where anyone can be mayor for a day.

Lovingly nick-named the "Brick Dick" this municipal tower was winner of the World's Most Phallic Building Contest.

These enduring murals depicting a distinctly Marxist tribute to capitalism could not even be defeated by McCarthyism.

The oldest working mechanical clock in the world.

The largest stone circle in the world has ended up bringing up more questions than it has answered.

A giant white horse drawn on an English hillside may not have been intended to be a horse at all.

Famously misunderstood wonder of the ancient world

A mysterious light in the wood, rumoured to be the the ghost of a railroad brakeman.