This irregularly shaped sea fortress has defended not one but three different sovereign states.

An abstract monument to a symphonic composer.

Tiny memorials honor individual victims of the Holocaust.

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

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

Where once there was a train station bathroom, there is now this German burger joint.

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

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

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

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

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

A bit of the Berlin Wall was gifted to the Icelandic capital to commemorate the 25th anniversary of German reunification.

This stunning concert hall has become a symbol of Iceland's national recovery.

One of the tallest buildings in Iceland, and perhaps, the most visually impressive.

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

This series of Baroque passageways in Vienna's cultural center mix old architecture with modern art.

Vienna's giant wonder wheel had a starring role in one of the greatest noir movies of all time.

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

The final resting place for the remains of 143 Habsburg royalty.

The topiary maze at the Habsburg hunting lodge.

Each year melting snow turns these Austrian hiking trails into scuba zones.

Bizarrely-painted church designed by a controversial artist.

A centuries old castle atop a dormant volcano houses museums devoted to both women and witches.

The shell of a medieval fortress offers commanding views of the area it once protected.