In the center of Wrocław's old meat market stands a somber tribute to the city's livestock.

While the U.S. and Soviet Union were engaged in a space race, Poland built a UFO on the ground.

An artificial hill and apparent calendric structure built in the Early Middle Ages immortalizes a legendary Polish princess.

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

A merchant court dedicated to the fictitious King Arthur is heavily adorned with bizarre Renaissance art.

These massive moving sand dunes have swallowed an entire village and are still on the run.

Poland's oldest surviving university building holds a wealth of historic science instruments including some used by Copernicus.

A striking public sculpture representing the period of martial law in Communist Poland.

A fairytale Gothic castle steeped in Nazi treasure conspiracy theories.

This Polish cave has housed a dragon, a brothel, and an enduring legend.

The walls and ceiling of this Polish church are decorated with thousands of skulls, with another 21,000 skeletons just below.

This floating sculpture of ice is a poignant reminder of nature's power.

The design of this beautifully crafted building was inspired by Norwegian glaciers.

Longest road tunnel in the world features an air treatment plant and the illusion of daylight.

One of the most breathtaking railways in Europe also takes one of the steepest climbs, from fjord to mountain plateau.

One man's exploration of the human form, including the bizarre and delightful "Man Attacked by Babies."

This gem from the industrial age helps visitors and residents alike traverse hilly Stockholm.

The Swedish flag over this small naval fort signals that the nation is at peace.

This poignant sculpture of a gnarled weapon is a symbol of non-violence.

Swedish skyscraper with a 90° twist.

The remains of Alfred Nobel's first nitroglycerine factory can still be found on the shores of a Swedish bay.

Stockholm's deepest subway station is also a stunning ecological wonder.

An ancient Viking runestone hidden in plain view in Stockholm's old town.

The library's graceful rotunda is like a bibliophile's temple.