The former home of the Nobel Prize-winning American writer is now home to dozens of six-toed cats.

The ancient Greek Titan guards this massive dam holding a lightning bolt to symbolize electricity.

The gorgeous library at Trinity College is home to remarkable treasures of Irish identity.

"Holy Wisdom" overlooks the city that became its namesake.

Sofia's legislative center is continuously reinventing itself.

A striking symbol of the Bulgarian capital.

A 12th-century fortress containing some of Berlin's oldest buildings.

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

Art and a pun, all in one.

An old department store turned Nazi prison turned artist commune.

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

The site of the famous Nazi book burning campaign of 1933 remembers its "Night of Shame".

The most visited, and possibly most controversial, museum in Germany.

The largest free-standing aquarium in the world resides in a hotel lobby in Berlin.

The oldest museum in Russia is home to a fascinating collection of nearly two million anthropological artifacts and anatomical curiosities.

A 250-year-old timepiece-automaton adorned with golden mechanical birds, which still sing to this day.

The deepest metro station in the world.

An Art Nouveau building covered in animal gargoyles and grotesques.

One of Antoni Gaudí's most classic buildings is well-known for its "dragon-back" design.