Minnesota's oldest and deepest mine is now an underground physics laboratory.

Home to a 26-foot-tall statue of an American icon.

Nicknamed the "Grand Canyon of the North," this open-pit mine in Minnesota has a much shorter history.

Where one of America's greatest songwriters lived before he was Bob Dylan.

The world's largest floating loon bobs in the lake to kick off an annual festival.

The famed architect designed this Minnesota gas station of the future with a lookout tower.

It's believed the soldier was 109 years old when he passed away.

This posh mansion began as a family's estate and ended as the site of a murder ripped from the pages of a pulp novel.

Home to part of the world’s largest private collection of original manuscripts and documents.

The watery grave of an impractical idea.

This rare vessel mixed luxury with labor before being converted to a museum and sometimes haunted maze.

A haunting army of decomposing, moss-covered stuffed animals and dolls guard this swinging truss.

A spooky defunct railroad tunnel now part of a sprawling trail.

This century-old barn is home to a homey, eclectic film festival.

This 25-foot-tall statue was built as a protest to a property dispute.

Madrid's romantically ornate crystal palace has been offering shelter to plants and art for over a century.

One of Madrid's oldest trees, with a long and colorful history, resides in El Retiro Park.

The Spanish king's private bathroom embraced the idea of a porcelain throne.

This macabre masterpiece of a mural is one of Francisco Goya's "Black Paintings."

A statue commemorating a beloved stray dog who was adopted by the entire neighborhood where he lived.