Milan's duomo is covered in beautiful carving including a curious "dinosaur-like" beast.

The secret medieval communication system will whisk your words above the noise of the crowd.

This poignant art installation raises awareness of violence against women.

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

A museum dedicated to the history of a terrifying secret police is now held in their former headquarters.

Dedicated to the European Sinti and Roma peoples murdered during the Holocaust.

This monumental work of art symbolizes the coming together of a previously divided city.

Metro station with a claim to rock n' roll fame.

Cold war icon and onetime "hole" in the iron curtain.

A tree-like building perches on its trunk in the Steglitz neighborhood of Berlin.

Gardens representing parts of Asia, Europe, and the Mid East are tucked away among the Soviet-style buildings in East Berlin.

A whimsical and twisted animatronic monster tour beneath the streets of Berlin.

These enormous, stern-faced statues greet visitors with lanterns, and sometimes costumes.

A subterranean house of worship carved right out of the bedrock.

On the Spree bank, discover one of the last reminders of a symbolic wall that divided, and was torn down by the people.

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

One of downtown Berlin's last reminders of its Communist past.

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

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

Baroque celebration of the end of the Great Plague of Vienna.

An interactive exhibition space dedicated to the kinetic sculptures of Swiss artist Jean Tinguely.

An ancient Roman theatre restored to its former glory in the Spanish city of Cartegena.

This artistic fountain display pays homage to this area's theatrical history.

It's good luck to be mocked by this monkey.