An eerie, derelict amusement park in Berlin.

America's most famous museum of medical oddities is home to the remains of Albert Einstein's brain.

A former Canadian automobile ferry mysteriously appeared in the Black River 20 years ago, and now it quietly rusts away.

An underground world of gorgeous, palatial metro stations designed as a nuclear shelter complex.

This picturesque cottage was the site of Ulysses S. Grant’s final and perhaps most important campaign.

The scant remains of this flooded historic village can be explored in one of the most remote areas of the Great Smokies.

Maine's oldest diner also happens to win acclaim for its elevated comfort food.

A bronze monument to Cleveland's favorite, fastest son.

On the upper deck of this church-owned parking garage stand eight pillars topped with different Catholic saints.

A Victorian-style home known as the “Castle on the Hill.”

The only museum dedicated entirely to the dry stone walling technique.

A chilling disappearance (and rescue) of a child uncovers a geological mystery.

On a remote island in the northern reaches of Lake Michigan, a museum of collectibles collides with a vintage toy store.

These dramatic cola-colored falls have appeared in a poem by Henry Wadsworth Longfellow and a song by Sufjan Stevens.

This magnificent 18th-century hall consists of a maze of nearly a thousand interconnected passages.

The early 20th-century home features cutting-edge technology of the day, such as ammonia refrigeration and needle showers.

This metro station doubles as an unintentional paleontology museum.

This massive stained-glass masterpiece is thought to be the largest Tiffany dome in existence.

With 3,000 bikes on display, the world's largest bicycle museum includes some famous rarities.

Once one of the most polluted caves in America, now an environmental success story and a museum dedicated to caves.

This lighthouse has been guiding shipping into the Golden Gate since before the American Civil War.

Hidden in the hills of Western Pennsylvania lies one of the best-kept ghost towns in America that you can legally visit.

This collection of 20th-century toys is filled with a lifelong personal toy collection brought from the U.S. to Amsterdam.

A living maritime paradox still floats in the same lake where it was built and resurrected... or was it?