Rebuilt remains of a temple to Roman god Mithras.

One of the few remaining casualties of the London Blitz, this destroyed church has become an enchanting public garden.

More than 5,000 contemporary and "historic" mustards from around the world.

Hidden away in the city of Madison, Wisconsin is a nearly forgotten home that Frank Lloyd Wright built for a childhood friend.

The only thing these street signs will help you navigate is your imagination.

The last original miniature duckpin bowling lanes in America, located in a Milwaukee dive bar.

This was once the largest four-sided clock in the world (yes, even bigger than Big Ben).

A giant, Gilded Age mansion that once belonged to the beer baron of Milwaukee.

A unique botanical garden housed in three giant geodesic domes.

Statue dedicated to the star of an old television show.

This striking art museum holds an amazing series of curiosity cabinets.

The first museum in the United States dedicated entirely to posters.

Cryptic messages embedded in the New York City sidewalk.

A tribute to a great Texas blues musician.

An 18-foot-tall troll sculpture, made from recycled wood and materials found in nature.

A view-altering observatory at the University of Texas.

Inside this Krakow church, an explosion of psychedelic color.

Remnants from a time before electricity.

Legend holds that this knife serves as a chilling reminder of the deadly rivalry between two local builder brothers.

A collection of modern and vintage pinball machines housed in the cellar of a 15th-century building.

An underground city of salt.

Krakow's own version of the Hollywood Walk of Fame.

Seven dragon statues—including one that breathes real fire—are scattered throughout the streets of Krakow.

St. Mary's features one of the most spectacularly decorated cathedral interiors in all of Europe.