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

A narrow passage next to a cafe leads to a courtyard exploding with murals, tags, and paste-ups.

Thousands of coffin-like pillars make up this controversial Holocaust memorial.

Fantastic views and thousands of love locks.

A history of heat is on display at this unique Austrian museum.

Vienna's diversity-themed traffic lights were inspired by the Eurovision Song Contest.

The Habsburgs' royal collections of art and wonders.

Legends surround an ancient tree trunk riddled with nails for good luck.

This museum promotes informed contraception by documenting its often secret past.

Beautiful Austrian natural history museum with carved ceilings and row after row of ancient taxidermy.

Op-art architecture designed for happiness.

The largest fountain in Bratislava.

This Slovakian statue of an emerging sewer worker might just be a bronze peeping tom.

An abandoned set from the 1980 film "Popeye," claimed and repurposed as a theme park by creative locals.

This Venice bookstore has resigned itself to constant flooding by keeping its books in bathtubs and boats.

Two very green residential towers cleaning the air in one of Europe's most polluted cities.

Suffocating dogs was a common spectacle in the fumes of this noxious cave.

San Gennaro, the patron saint of Naples, greets pedestrians between these narrow city streets.

A surreal botanical garden with an even more surreal tour guide.

Elaborately carved to showcase the glorious wealth that the age of exploration brought to the Portuguese empire.

This restored Portuguese cafe may well be the most beautiful place in the world to grab a Big Mac.

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

Commonly acknowledged as the only public monument to the Devil himself.

An ancient Egyptian temple in the middle of Madrid, Spain.